Bitcoin Wiki - User contributions [en]

HostingBuY

2016-05-19T04:12:27Z

Sunnankar: /* History */

{{Infobox company|
| name = HostingBuY
| image = [[File:Hostingbuy.png|272px]]
| logo = [[Image:Hostingbuy.png]]
| type = [[Limited liability company|LLC]]
| location = [[Nis]], [[Serbia|Serbia]]
| slogan = Think Differently, Work Simpler.
| type = [[Privately held company|Private]]
| services = [[Dedicated hosting service|Dedicated Servers]] [[Colocation centre|Colocation]] [[Cloud hosting]] [[Content Delivery Network]] Hybrid Solutions
| industry = [[Internet hosting service|Hosting]]|
| foundation = {{Start date|[[January]], [[2010|2010]]}}
|founder=[http://www.nmocv.com Nenad Mladenovic]
| employees = 5+
| area_served = Worldwide
| homepage = [https://www.hostingbuy.net| HostingBuY]
| website = [https://www.hostingbuy.net www]
| twitter = hostingbuy
| facebook = hostingbuy
| linkedin = hostingbuy
| instagram = hostingbuy
| alexa = {{IncreaseNegative}} 866,520 ({{as of|2016|5|16|alt=May 2016}})<ref name="alexa">{{cite web|url= http://www.alexa.com/siteinfo/hostingbuy.net |title= HostingBuY Site Info | publisher= [[Alexa Internet]] |accessdate= 2016-05-16 }}</ref>
}}

HostingBuY is a Private Internet hosting service company with offices in [[Europe|Europe]]. The company offers hosting-related services and well as many other modern business solutions.

From the beginning to this days HostingBuY prefers payment in [[Bitcoin|Bitcoin]] currency. [[Blockchain.info|Blockchain]] by the end of 2011 was on testing and integration [[BitPay|BitPay]] service that today using.

== History ==
Let us go back in 2010 when wasn't had a global network access and partners which has today. On 14.January.2010 registered first domain .me and created internet name HostingBuY Me. One year later on 6.February.2011 registered domain .net changed and removed '''.me''' from the name, and new global brand name '''HostingBuY''' was born.

First year worked as reseller for other company, mid-year in 2011 rent first Dedicated Servers and business have changing and growing. Next years actively worked on respect for clients, was preserving and was growing brand in the global internet market.

On 28.August.2014, the company was founded and opened, with one website, an online global market [[business directory]]. Client companies could add their contact details and a short description. The company started to designing custom [https://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ cloud hosting] and [[Hybrid_server|Hybrid Solutions]] and more modern additional service. Office and headquarters base in [[Serbia]],[[Nis]]. The company eventually focused solely on hosting services.

Today HostingBuY is stable and growing company, success based on the philosophy of combining excellent quality product at affordable price points with a first-class network, together with a highly skilled engineering and technical support team.

== Business model ==
HostingBuY provides its customers to prefers all in one where they can obtain a [[domain name]], [[IP addresses]], [[colocation centre|housing]]. In the offer can be found diverse solutions, like as Cloud business applications [[Office_365|Office 365]], [[Google_Apps_for_Work|Google Apps]] and many other. Private Online backup [[R1Soft|R1Soft]] and custom solutions for private and security storage space like [[Dropbox_(service)|Dropbox]].

A huge variety of available [[Dedicated Servers|dedicated]] and vps servers, which can be choice on rack units, private racks and cage. Monitoring and managing remote administration 24/7/365 on-demand and customer needs.
Shared Web hosting, audio and video streaming solutions, domain registration large selection available SSL certificates.

== Network and datacenters ==
The company is authorized partner with one of big global Data centers gives better features and performance. ISO certified data centers at strategic locations across the globe to ensure prime access to the major business areas in [[Europe]], ( [[Netherlands|Netherlands]], [[Germany|Germany]],), the [[United States]] ( [[Washington DC|Washington DC]], [[San Francisco|San Francisco]], [[Dallas|Dallas]] ) and [[Asia]] ( [[China|China]], [[Singapore|Singapore]] ). Each one is designed to the highest specifications for performance, reliability and security.

== Solutions ==

Check Trade based list [[Trade | list of providers]] that you can check some of the parts where the company provides services and accept bitcoin payments.

{| class="wikitable sortable" style="width: auto; text-align: center; font-size: smaller; table-layout: fixed;"
! Name
! Price
! Bandwidth
! IPv6
! RAM
! Disk
! Location
! TOR
! Notes
|-
| [http://www.hostingbuy.net/ HostingBuY]
| 16.74 $
| 4 TB
| {{yes}}
| 1024MB
| 40GB '''(RAID 10)'''
| Netherlands, Germany, United States, Singapore
| TOR is allowed
|
|-
|}

==Payment methods==

{| class="wikitable" style="width: auto; text-align: center; font-size: smaller; table-layout: fixed;"
! [[Bitcoin|Bitcoin]]
! [[Litecoin|Litecoin]]
! [[PayPal|PayPal]]
! [[Neteller|Neteller]]
! [[ePayments|ePayments]]
! [[Payoneer|Payoneer]]
! [[WebMoney|WebMoney]]
! [[Skrill|Skrill]]
! [[Perfect Money|Perfect Money]]
! [[OKPAY|OKPAY]]
! [[Payza|Payza]]
! [[Paymentwall|Paymentwall]]
! [[Bank wire|Bank wire]]
|}

==References==
<References />
{{reflist}}
{{reflist|30em}}

* [https://airbitz.co/biz/7646/hostingbuy/ https://airbitz.co/biz/7646/hostingbuy/]
* [http://www.bitpages.co/listing/hostingbuy.html http://www.bitpages.co/listing/hostingbuy.html]
* [http://betteroffbitcoin.com/how-to-use-bitcoin-to-setup-a-self-sustaining-anonymous-website/ http://betteroffbitcoin.com/how-to-use-bitcoin-to-setup-a-self-sustaining-anonymous-website/]
* [http://www.slideshare.net/berniejcoyle/purchasing-domain-names-with-bitcoins http://www.slideshare.net/berniejcoyle/purchasing-domain-names-with-bitcoins]
* [http://bitcoinbestmall.com/hostingbuy http://bitcoinbestmall.com/hostingbuy]

==External links==
* [https://www.hostingbuy.net/ Official website]

'''Social network profile'''
* [https://www.facebook.com/hostingbuy Facebook]
* [https://twitter.com/hostingbuy Twitter]
* [https://www.linkedin.com/company/hostingbuy LinkedIn]
* [https://www.instagram.com/hostingbuy/ Instagram]

[[Category:Companies]]
[[Category:Web hosting]]
[[Category:Internet hosting]]
[[Category:Cloud computing providers]]
[[Category:Domains]]
[[Category:Email hosting]]
[[Category:Virtual hosting]]
[[Category:Cloud storage]]
[[Category:Data centers]]
[[Category:Companies based in Niš]]
[[Category:Bitcoin]]

Bitcoincloudservices

2016-05-19T04:10:58Z

Sunnankar:

Bitcoin Cloud Services (BTC Cloud Services LTD) is a Bitcoin Foundation Silver Member and UK incorporated entity. They provide affordable [https://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ Bitcoin cloud mining contracts] with live technical Support, no hidden fees, and instant mining contract delivery. Bitcoin cloud services sells hashing power by the gigahash (GH/s), has no pool fees, and offers daily payouts.

Bitcoin Cloud Services sells hashing power by the Gighash (GH/s)
Contract length is 5 years
Minimum contract purchase of 50 GH/s
Maximum contract purchase of 70 TH/s

==External Links==

* Website [https://www.bitcoincloudservices.com/ Bitcoincloudservices.com]

[[Category:Mining contractors]]
[[Category:Mining]]
[[Category:Mining contracts]]
[[Category:ASIC mining]]

Pyramining

2016-05-19T04:10:10Z

Sunnankar:

[http://www.pyramining.com/ Pyramining] is a [https://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ bitcoin mining contractor] that lets you borrow hashing power to mine for bitcoins '''without having to buy, set up and maintain your equipment'''. You join by sending some bitcoins through a referral link, and are rewarded with at least 10% return on your investiment. Once your account is active, miners will keep working for you until you are fully rewarded. Currently receiving a full reward on your investment will take about 24 months. A referral system is used to allow a more rapid increase in total system hashrate and revenues.

== How does it work? ==

Join through a referral link. Active referral links can be found [https://sites.google.com/site/pyramining/ on this page], on [https://twitter.com/Pyramining the Pyramining Twitter feed] and at the [http://www.links-pyramining.com/ Pyramining Referral Links service]. Once you have joined, specify the bitcoin address of your wallet where your mining rewards is to be sent, and deposit any amount of bitcoins to the provided address. If you like, you can then invite people to join through your own referrals to increase your rewards.

== Is it a pyramid scheme? ==

No. Pyramining is a mining contractor. Rewards come entirely from bitcoin mining. The referral system provides the opportunity to increase income by recruiting new members and to increase hash rate by having more members. By using one of the referral links on this page you will give a small benefit to the person who wrote this wiki! Read the FAQ on the Pyramining site for more details.

== External links ==

* [http://www.pyramining.com/ Pyramining main site]
* [https://sites.google.com/site/pyramining/ Always-updated Pyramining referral links]
* [https://twitter.com/Pyramining Pyramining Twitter feed]
* [http://www.links-pyramining.com/ Pyramining Referral Links service]
* [http://pyramining-referral-links.com/ Pyramining Referral Links]

[[Category:Mining]]
[[Category:Mining contractors]]

BitcoinFrenzy

2016-05-19T04:09:29Z

Sunnankar:

'''BitcoinFrenzy''' sells [https://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ mining contracts] in 1 Gigahash units with Fixed & Indefinite contract types.

Fixed Contract - 1 and 2 year period .

Indefinite Contract comes with revenue reinvestment program

The service is quoted to begin mining in September 2013<ref>[http://www.bitcoinfrenzy.com/pricing/]</ref>. They plan to operate [[KnCMiner]] Rigs. Current Hash rate on preorder with KncMiner is 6300 GH/s.

==External Links==

* Website [http://www.bitcoinfrenzy.com/ BitcoinFrenzy.com]

==References==
<references />

[[Category:Mining contractors]]
[[Category:Mining]]
[[Category:Mining contracts]]
[[Category:ASIC mining]]

Minerlease

2016-05-19T04:08:42Z

Sunnankar: /* Minerlease */

== Minerlease ==

Sells [https://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ mining contracts] in 1, 0.5 or 0.2 Gigahash units.

The service is quoted to begin mining in September 2013<ref>[http://www.minerlease.com/contracts/1year/]</ref>. They use BFL rigs initially due to its low power consumption. Current Hash rate on preorder with BFL is 5 Thash.

==External Links==

* [http://www.minerlease.com Website]

==References==
<references />

[[Category:Mining contractors]]
[[Category:Mining]]
[[Category:Mining contracts]]
[[Category:ASIC mining]]

Category:Mining contractors

2016-05-19T04:07:53Z

Sunnankar:

Provides mining services with performance specified by contract. For example, a specific level of mining capacity may be rented out for a set price for a specific duration. Mining shares provide Mining as a Service (MaaS). These break large-scale datacenter mining down to easily manageable pieces that are available in the form of shares of equipment.

Hosted mining services and [https://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ Cloud Mining] create systemic risk for Bitcoin because they undermine the security assumption that the control of mining power is well-distributed. If too much hashrate is consolidated in large hosting centres, an attacker is more-easily able to compromise a significant portion of it and could potentially disrupt Bitcoin or steal back their own spent money.

[[Category:Mining]]

Genesis Mining

2016-05-19T04:05:50Z

Sunnankar: /* History */

{{infobox company|image=[[File:Genesis-mining-logo.png|225px]]
|industry=Bitcoin Mining
|foundation=February, 2014
|website=https://www.genesis-mining.com/
}}

'''Genesis Mining''' is a company that sells bitcoin [[mining]] contracts and is currently one of the largest [[cloud mining]] companies in the world.<ref>{{cite web|title=Genesis Mining – Examining The Largest Scrypt Cloudmining Provider|url=https://www.cryptocoinsnews.com/genesis-mining-explaining-largest-scrypt-cloudmining-provider/|publisher=CryptoCoinsNews|accessdate=19 May 2015}}</ref><ref>{{cite web|title=The magic of mining|url=http://www.economist.com/news/business/21638124-minting-digital-currency-has-become-big-ruthlessly-competitive-business-magic|publisher=The Economist|accessdate=19 May 2015}}</ref> The company is active in the Bitcoin community and is frequently seen at events across the world including in Paris, New Zealand, Los Angeles, New York City, Hong Kong.<ref>{{cite web|title=How the ”Impossible” Became the Future: A Talk with Genesis Mining’s Marco Streng|url=http://cointelegraph.com/news/111394/how_the_impossible_became_the_future_a_talk_with_genesis_mining_s_marco_streng|publisher=CoinTelegraph|accessdate=19 May 2015}}</ref>

==History==
The company was formed after the three founding partners realized there was a need for a legitimate [https://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ cloud mining] provider in an industry full of fraudulent companies.<ref>{{cite web|title=History of Genesis Mining|url=http://cloudminingdirectory.com/genesis-mining/review/|publisher=Cloud Mining directory|accessdate=19 May 2015}}</ref> From there they set out to offer [[cloud mining]] services to active users and new mainstream users. Genesis Mining launched in February of 2014.<ref>{{cite web|title=Spondoolies-Tech and Genesis Team Up for Cloud Mining Service|url=http://www.coindesk.com/spondoolies-tech-genesis-team-new-cloud-mining-service/|publisher=[[CoinDesk]]|accessdate=19 May 2015}}</ref>

==Services==
Their services allow customers to purchase mining contracts, which allow them to mine Bitcoin and [[altcoin]] through a cloud-based computer network.<ref>{{cite web|title=Genesis-Mining : Start Mining For As Low As 14 Cents Per Kilohash – Bitcoin 2014 Interview|url=http://digitalmoneytimes.com/crypto-news/2014518genesis-mining-start-mining-for-as-low-as-14-cents-per-kilohash-bitcoin-2014-interview/|publisher=Digital Money Times|accessdate=19 May 2015}}</ref> Their mining farms are based in Iceland, Canada, and Bosnia.<ref>{{cite web|title=Genesis Mining: A Cloud Scrypt Mining Provider|url=http://bitcoinist.net/genesis-mining-a-cloud-scrypt-mining-provider/|publisher=Bitcoinist|accessdate=19 May 2015}}</ref>

Genesis Mining offers [[scrypt]] and sha256 mining. Coins that can be mined (directly or indirectly by auto-conversion) include inter-alia:
* [[Bitcoin]]
* [[Litecoin]]
* Dash
* Dogecoin
* Monero

==External links==
[[File:Mining Farm of Genesis Mining.jpg|thumb|A mining farm of Genesis Mining located in Iceland. The picture shows mainly Zeus scrypt miners.]]
*[https://www.genesis-mining.com/ Genesis Mining website]
*[http://blog.genesis-mining.com/ Blog]
*[https://www.facebook.com/GenesisMining?fref=nf Facebook]
*[https://twitter.com/genesismining Twitter]

==References==

Mining rig

2015-12-10T18:25:14Z

Sunnankar: /* See Also */ Fix dead link

A '''mining rig''' is a computer system used for [[How_bitcoin_works#Bitcoin_mining|mining bitcoins]]. The rig might be a dedicated miner where it was procured, built and operated specifically for mining or it could otherwise be a computer that fills other needs, such as performing as a gaming system, and is used to mine only on a part-time basis.

'''Warning:''' GPU mining is not very profitable (if at all) anymore, and even if you have free electricity, GPU rigs will likely never pay for themselves at this point!

[[{{ns:file}}:Quick-and-dirty-4x5970-cooling.jpg|thumb|4x5970 Mining rig http://blog.zorinaq.com/?e=47]]
==Tips==

* Motherboards with on-board graphics (also referred to as integrated graphics) often are either problematic or unusable when more than one GPU card is installed. Choose a motherboard with no on-board graphics.
* The following component lists might be used to help in building a new rig. To minimize shipping costs, components from the same supplier were preferred over compenents from the least expensive source.

==Typical Dedicated Miner Configurations Using a Tower==

===One ATI 5830, Approximately 245 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || n/a || n/a || n/a
|-
| Power Supply || Rosewill Green Series RG530-S12 530W, 80 PLUS Certified || [http://www.newegg.com/Product/Product.aspx?Item=N82E16817182199 NewEgg] || $50
|-
| Motherboard || Foxconn M61PMP-K AMD || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813186189&Tpk=m61pmp NewEgg] || $45
|-
| CPU || AMD Sempron 145 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888 NewEgg] || $39
|-
| Memory || 2GB DDR3 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820146744 NewEgg] || $13
|-
| Graphics card || Radeon HD 5830 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16814102878 NewEgg] ($153) || $110
|-
| Case Fan || n/a || n/a || n/a
|-
| Storage || Western Digital Caviar 80GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822136292 NewEgg] || $17
|-
| Media Drive || DVD Rom Drive || n/a || n/a
|-
| Keyboard, Mouse and Display || n/a || n/a || n/a
|-
| Total || (Approx: $1.1755 /Mhash) || || $285 + s/h/t
|}

===Three ATI 5770s, Approximately 630 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Power Supply || Rosewill Green Series RG530-S12 530W, 80 PLUS Certified || [http://www.newegg.com/Product/Product.aspx?Item=N82E16817182199 NewEgg] || $50
|-
| Motherboard || ASRock 890GX EXTREME4 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813157207 NewEgg] || $125
|-
| CPU || AMD Sempron 145 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888 NewEgg] || $39
|-
| Memory || 2GB DDR3 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820146744 NewEgg] || $13
|-
| Graphics card || Sapphire Radeon HD5770 1GB DDR5 || [http://www.superbiiz.com/detail.php?name=AT-5770V3&title=Sapphire-Radeon-HD5770-1GB-DDR5-2DVI-HDMI-DisplayPort-PCI-Express-Video-Card superbiiz] || $339 ($113 x 3)
|-
| Storage || Western Digital Caviar 80GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822136292 NewEgg] || $17
|-
| Total || (Approx: $1.0412 /Mhash) || || $583 + s/h/t
|}

===Two ATI 5850s, Approximately 600 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || n/a || n/a || n/a
|-
| Power Supply || CORSAIR Builder Series CX600 V2 600W , 80 PLUS Certified || [http://www.newegg.com/Product/Product.aspx?Item=N82E16817139028 NewEgg] || $70
|-
| Motherboard || MSI 870-G45 AM3 AMD 770 ATX || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813130290 NewEgg ($5 more)] || $70
|-
| CPU || AMD Sempron 145 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888 NewEgg] || $39
|-
| Memory || 2GB DDR3 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820146744 NewEgg] || $13
|-
| Graphics card || Sapphire Radeon HD 5850 XTREME || $322 ($161 x 2)
|-
| Case Fan || n/a || n/a || n/a
|-
| Storage || Western Digital Caviar 80GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822136292 NewEgg] || $17
|-
| Media Drive || DVD Rom Drive || n/a || n/a
|-
| Keyboard, Mouse and Display || n/a || n/a || n/a
|-
| Total || (Approx: $0.8917 /Mhash) || || $531 + s/h/t
|}

===Three ATI 5850s, Approximately 900 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || n/a || n/a || n/a
|-
| Power Supply || PC Power & Cooling Silencer Mk II 950W, 80 PLUS Silver Certified || [http://www.directron.com/ppcmk2s950.html Directron] || $120
|-
| Motherboard || MSI 890FXA-GD70 || || $195
|-
| CPU || AMD Sempron 145 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888 NewEgg] || $39
|-
| Memory || 2GB DDR3 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820146744 NewEgg] || $13
|-
| Graphics card || Sapphire Radeon HD 5850 XTREME || || $483 ($161 x 3)
|-
| Case Fan || n/a || n/a || n/a
|-
| Storage || Western Digital Caviar 80GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822136292 NewEgg] || $17
|-
| Media Drive || DVD Rom Drive || n/a || n/a
|-
| Keyboard, Mouse and Display || n/a || n/a || n/a
|-
| Total || (Approx: $0.9677 /Mhash) || || $877 + s/h/t
|}

===Three ATI 6990s, Approximately 2.1 Ghash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || CoolerMaster HAF X || || $179
|-
| Power Supply || SILVERSTONE ST1500 1500W, 80 PLUS Silver Certified || [http://www.newegg.com/Product/Product.aspx?Item=N82E16817256054&Tpk=silverstone%201500w Newegg] || $365
|-
| Motherboard || MSI 890FXA-GD70 || || $195
|-
| CPU || AMD Sempron 145 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888 NewEgg] || $39
|-
| Memory || 2GB DDR3 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820146744 NewEgg] || $13
|-
| Graphics card || 3 * Radeon HD 6990 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16814125370&cm_re=6990-_-14-125-370-_-Product NewEgg] || $2220 ($740 × 3)
|-
| Storage || Western Digital Caviar 80GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822136292 NewEgg] || $17
|-
| Keyboard, Mouse and Display || n/a
|-
| Total || (Approx: $1.4438 /Mhash) || || $3,028 + s/h/t
|}

==Typical Dedicated Miner Configurations Using a Rack Mount==

===Budget AMD Sempron / Dual ATI 6990: Approximately 1.4 Ghash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || IPC-4370S 4U || [http://www.plinkusa.net/web4038.htm P-Link Computer] || $85 (incl s/h)
|-
| Power Supply || PC Power & Cooling Silencer Mk II 950W, 80 PLUS Silver Certified || [http://www.directron.com/ppcmk2s950.html Directron] || $120
|-
| Motherboard || MSI 870-G45 AM3 AMD 770 ATX || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813130290 NewEgg ($5 more)] || $70
|-
| CPU || AMD Sempron 145 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888 NewEgg] || $39
|-
| Memory || 2GB DDR3 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820146744 NewEgg] || $13
|-
| Graphics card || 2 * Radeon HD 6990 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16814125370&cm_re=6990-_-14-125-370-_-Product NewEgg] || $1480 ($740 × 2)
|-
| Storage || Western Digital Caviar 80GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822136292 NewEgg] || $17
|-
| Keyboard, Mouse and Display || n/a
|-
| Total || (Approx: $1.3057 /Mhash) || || $1,824 + s/h/t
|}

==Typical Multipurpose Miner Configurations==

===High-end Intel-based miner/gaming rig: single ATI 6990, Approximately 750 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || CoolerMaster HAF 932 || || $140
|-
| Power Supply || PC Power & Cooling Silencer Mk II 950W, 80 PLUS Silver Certified || [http://www.directron.com/ppcmk2s950.html Directron] || $120
|-
| Motherboard || MSI P67A-GD65 || || $173
|-
| CPU || Intel Core i7-2700K || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819115095 NewEgg] || $340
|-
| Memory || G.SKILL ECO Series 8GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820231403 NewEgg] || $55
|-
| Graphics card || Radeon HD 6990 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16814150529&cm_re=6990-_-14-150-529-_-Product NewEgg] || $734
|-
| Heat Sink Fan || CoolerMaster Hyper212+ || [http://www.newegg.com/Product/Product.aspx?Item=N82E16835103065&cm_re=hyper_212-_-35-103-065-_-Product NewEgg] || $40
|-
| Storage || Seagate 1TB 7200RPM HDD || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822148433 NewEgg] || $70
|-
| Media Drive || ASUS DVD-RW || [http://www.newegg.com/Product/Product.aspx?Item=N82E16827135204 NewEgg] || $22
|-
| Keyboard || LITE-ON SK-1788/BS PS/2 Keyboard || [http://www.newegg.com/Product/Product.aspx?Item=N82E16823107120 NewEgg] || $8
|-
| Mouse || V7 M30P20-7N PS/2 Mouse || [http://www.newegg.com/Product/Product.aspx?Item=N82E16826575002 NewEgg] || $7
|-
| Display || LG IPS231P-BN Black 23" 6ms IPS || [http://www.newegg.com/Product/Product.aspx?Item=N82E16824005234 NewEgg] || $250
|-
| Total || || || $1949 + s/h/t
|}

===High-end AMD-based miner/gaming rig: single ATI 6990, Approximately 750 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || CoolerMaster HAF 932 || || $140
|-
| Power Supply || PC Power & Cooling Silencer Mk II 950W, 80 PLUS Silver Certified || [http://www.directron.com/ppcmk2s950.html Directron] || $120
|-
| Motherboard || Biostar TA990FXE || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813138341 NewEgg] || $130
|-
| CPU || AMD FX-8150 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103960 NewEgg] || $250
|-
| Memory || G.SKILL ECO Series 8GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820231403 NewEgg] || $55
|-
| Graphics card || Radeon HD 6990 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16814150529&cm_re=6990-_-14-150-529-_-Product NewEgg] || $734
|-
| Heat Sink Fan || CoolerMaster Hyper212+ || [http://www.newegg.com/Product/Product.aspx?Item=N82E16835103065&cm_re=hyper_212-_-35-103-065-_-Product NewEgg] || $40
|-
| Storage || Seagate 1TB 7200RPM HDD || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822148433 NewEgg] || $70
|-
| Media Drive || ASUS DVD-RW || [http://www.newegg.com/Product/Product.aspx?Item=N82E16827135204 NewEgg] || $22
|-
| Keyboard || LITE-ON SK-1788/BS PS/2 Keyboard || [http://www.newegg.com/Product/Product.aspx?Item=N82E16823107120 NewEgg] || $8
|-
| Mouse || V7 M30P20-7N PS/2 Mouse || [http://www.newegg.com/Product/Product.aspx?Item=N82E16826575002 NewEgg] || $7
|-
| Display || LG IPS231P-BN Black 23" 6ms IPS || [http://www.newegg.com/Product/Product.aspx?Item=N82E16824005234 NewEgg] || $250
|-
| Total || || || $1832 + s/h/t
|}

===Mid-level AMD-based miner/gaming/workstation rig: single ATI 6870, Approximately 300 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || CoolerMaster Centurion 5 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16811119068 NewEgg] || $50
|-
| Power Supply || Antec Earthwatts EA-650 GREEN 650W, 80 PLUS BRONZE certified || [http://www.newegg.com/Product/Product.aspx?Item=N82E16817371044 NewEgg] || $65
|-
| Motherboard || MSI 970A-G46 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813130637 NewEgg] || $90
|-
| CPU (incl. stock heatsink + fan)|| AMD FX-6200 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819106010 NewEgg] || $169
|-
| Memory || G.SKILL Value Series 4GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820231396 NewEgg] || $23
|-
| Graphics card || Radeon HD 6870 || || $165
|-
| Storage || Seagate 1TB 7200RPM HDD || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822148433 NewEgg] || $70
|-
| Media Drive || ASUS DVD-RW || [http://www.newegg.com/Product/Product.aspx?Item=N82E16827135204 NewEgg] || $21
|-
| Keyboard || LITE-ON SK-1788/BS PS/2 Keyboard || [http://www.newegg.com/Product/Product.aspx?Item=N82E16823107120 NewEgg] || $8
|-
| Mouse || V7 M30P20-7N PS/2 Mouse || [http://www.newegg.com/Product/Product.aspx?Item=N82E16826575002 NewEgg] || $7
|-
| Display || HANNspree By Hanns-G HF225DPB 21.5" || [http://www.newegg.com/Product/Product.aspx?Item=N82E16824262011 NewEgg] || $120
|-
| Total || || || $798 + s/h/t
|}

===Mid-level Intel-based miner/gaming/workstation rig: single ATI 6870, Approximately 300 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || CoolerMaster Centurion 5 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16811119068 NewEgg] || $50
|-
| Power Supply || Antec Earthwatts EA-650 GREEN 650W, 80 PLUS BRONZE certified || [http://www.newegg.com/Product/Product.aspx?Item=N82E16817371044 NewEgg] || $65
|-
| Motherboard || MSI Z68A-G45 (B3) || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813130618R NewEgg] || $103
|-
| CPU (incl. stock heatsink + fan)|| Intel Core i5-2500K || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819115072 NewEgg] || $214
|-
| Memory || G.SKILL Value Series 4GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820231396 NewEgg] || $23
|-
| Graphics card || Radeon HD 6870 || || $165
|-
| Storage || Seagate 1TB 7200RPM HDD || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822148433 NewEgg] || $70
|-
| Media Drive || ASUS DVD-RW || [http://www.newegg.com/Product/Product.aspx?Item=N82E16827135204 NewEgg] || $21
|-
| Keyboard || LITE-ON SK-1788/BS PS/2 Keyboard || [http://www.newegg.com/Product/Product.aspx?Item=N82E16823107120 NewEgg] || $8
|-
| Mouse || V7 M30P20-7N PS/2 Mouse || [http://www.newegg.com/Product/Product.aspx?Item=N82E16826575002 NewEgg] || $7
|-
| Display || HANNspree By Hanns-G HF225DPB 21.5" || [http://www.newegg.com/Product/Product.aspx?Item=N82E16824262011 NewEgg] || $120
|-
| Total || || || $873 + s/h/t
|}

==See Also==

* [[Mining Hardware Comparison]]
* [http://coinminingrigs.com/ GPU Rig Assembly Guides]
* [https://www.weusecoins.com/en/mining-guide/ Getting Started With Bitcoin Mining]
* [https://www.bitcoinmining.com Bitcoin Mining]
* [https://www.youtube.com/watch?v=GmOzih6I1zs Video: What is Bitcoin Mining?]
* [http://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ Research, Review and Compare Cloud Mining Contracts]
* [http://bitcoinminer/ Bitcoin Miner]
* [https://rigsmonitoring.com/ RigsMonitoring]

[[Category:Mining]]

Mining Explorer

2015-12-08T03:32:45Z

Sunnankar: /* External Links */

==Description==

Mining Explorer [http://miningexplorer.org website], [http://miningexplorer.org/files/MiningExplorer.zip DOWNLOAD]

Monitoring tool for bitcoin mining. Developed in cooperation with bitcoin pool [[50BTC]]

'''Screenshots:'''

[[File:Mining_Explorer_screenshot1.png|400px]]
[[File:Mining_Explorer_screenshot2.png|400px]]
[[File:Mining_Explorer_screenshot3.png]]

To start the work choose the sign of gear in the settings, choose the necessary pool, enter API key, press OK and after that the program will start to show statistics. You can enter the keys for several pools, so you can choose the pool in the main window.

The program does not need installation, it can be dearchived and you can have it on flash drive. All the keys and settings can be saved in the configuration file. All the questions,remarks and suggestions about the program you can write in this thread.

==Application features==

* Monitoring of the Bitcoin`s rate( with Mt.Gox)
* Monitoring of the worker`s status (online/offline)
* Monitoring of the pool score
* Monitoring of the other settings, which pools give back on statistics
* The time of the last share, the time of connecting to the pool, etc. is taken into account the time zone on your computer
* Ability to save the width and position of the table columns

==List of the supported pools==

* 50BTC.com
* ABCPool
* BitClockers
* BTC Guild
* BTC mine
* Deepbit
* EclipseMS
* Itzod
* Mkalinin
* Mt.Red
* OzCoin
* Slush
* TripleMining

==Supported languages==

* English
* Russian
* German

==Version hystory==

'''Version 0.5.0''':

:In the balance window with the shortened information for BTCGuild appears "unpaid_rewards" instead of "total_rewards"

'''Version 0.4.9''':

:Formatted output balance and speed
:Correct display of balance for BTCGuild

'''Version 0.4.8''':

: Fixed bug saving width and column positions
: Added a separate display of invalid and stale shares for pool 50BTC

'''Version 0.4.7''':

: Fixed bug display workers Eclipse pool in "Custom" table

'''Version 0.4.6''':

: Fixed bug of choice "standard/custom window", "display of balance," "alignment of cells"

'''Version 0.4.5''':

: Added an optional choice of displaying the balance in the window on tray
: Added optional ability to align the content of table cells in the center of the cell

'''Version 0.4.4''':

: Automatically change the width of the window with a summary

'''Version 0.4.3''':

: Added pool TripleMining
: Added an optional choice of standard/custom application window
: Ability to move a window with basic information on tray

'''Version 0.4.2''':

: Fixed display data in a twisted form of Deepbit and BTCMine
: Improved exception handling in case of invalid input API key, incomplete data from the pool

'''Version 0.4.1''':

: Fixed bug rolling window

'''Version 0.4''':

: A summary table of workers from the different pools
: Opportunity to close the window with the basic information above the tray
: Minimization of the application to the taskbar, minimize to tray, close the application in the context menu
: Changed the design of the application

'''Version 0.3''':

: API for Itzod was corrected. Now you need to enter UserName_Key for an API key
: It is possible to minimize a window in tray and display the window with the basic information
: Sound notification when connecting / disconnecting
: To order the information click on the column header

'''Version 0.2''':

: Pools are added:
: * ABCPool
: * Mkalinin
: * Itzod
: The time of the last share, the time of connecting to the pool, etc. is taken into account the time zone on your computer
: Ability to save the width and position of the table columns

'''Version 0.1''':

: The initial version of the program

==FAQ==
Q: Why do I sometimes do not get the data with BTCGuild and on the top of the screen appears "Too often". 
A: MTC Guild let get API not more than once per minute. If you frequently access to the API in the program "Mining Explorer", next to the course MtGox, displayed a red label "Too often".

Q: Why is there no field roundduration in the pool information http://pool.mkalinin.ru/api.php . 
A: There is no field Roundduration , because it displays the current time UTC +0, and not the duration of the round.

Q: Why is the information about the workers of the pool http://pool.itzod.ru not displayed? 
A: The pool http://pool.itzod.ru gives the information only about the active workers. If there are no workers then there is nothing to give.

==External Links==

* http://miningexplorer.org/en/ Mining Explorer website
* https://50btc.com/ mining pool 50BTC.com
* [http://bitcoinminer.com Bitcoin Miner]
* [https://www.bitcoinmining.com Bitcoin Mining]

Pooled mining

2015-12-08T03:32:02Z

Sunnankar: /* References */

'''Pooled mining''' is a [[Mining|mining]] approach where multiple generating clients contribute to the generation of a block, and then split the block reward according the contributed processing power. Pooled mining effectively reduces the granularity of the block generation reward, spreading it out more smoothly over time.

==Introduction==

With increasing generation difficulty, mining with lower-performance devices can take a very long time before block generation, on average. For example, with a mining speed of 1000 Khps, at a difficulty of 14484 (which was in effect at the end of December, 2010), the average time to generate a block is almost 2 years.

To provide a more smooth incentive to lower-performance miners, several pooled miners, using different approaches, have been created. With a mining pool, a lot of different people contribute to generating a block, and the reward is then split among them according to their processing contribution. This way, instead of waiting for years to generate 50btc{{Citation needed}} in a block, a smaller miner may get a fraction of a Bitcoin on a more regular basis.

A '''share''' is awarded by the mining pool to the clients who present a valid [[proof of work]] of the same type as the proof of work that is used for creating [[block|blocks]], but of lesser difficulty, so that it requires less time on average to generate.

==Pooled mining approaches==

The problem with pooled mining is that steps must be taken to prevent cheating by the clients and the server. Currently there are several different approaches used.

===The slush approach===

[[Bitcoin Pooled Mining]] (BPM), sometimes referred to as "slush's pool", follows a score-based method. Older shares (from beginning of the round) have lower weight than more recent shares, which reduces the motivation to cheat by switching between pools within a round.

===The Pay-per-Share approach===

The Pay-per-Share (PPS) approach, first described by [[BitPenny]], is to offer an instant flat payout for each share that is solved. The payout is offered from the pool's existing balance and can therefore be withdrawn immediately, without waiting for a block to be solved or confirmed. The possibility of cheating the miners by the pool operator and by timing attacks is thus completely eliminated.

This method results in the least possible variance for miners while transferring all risk to the pool operator. The resulting possibility of loss for the server is offset by setting a payout lower than the full expected value.

===Luke-Jr's approach ("[[Eligius]]")===
[[User:Luke-Jr|Luke]] came up with a third approach borrowing strengths from the earlier two.
Like slush's approach, miners submit proofs-of-work to earn shares.
Like puddinpop's approach, the pool pays out immediately via block generation.
When distributing block rewards, it is divided equally among all shares since the last valid block.
Unlike any preexisting pool approach, this means that the shares contributed toward stale blocks are recycled into the next block's shares.
In order to spare participating miners from transaction fees, rewards are only paid out if a miner has earned at least 0.67108864 BTC (400 [[Tonal Bitcoin|TBC]]). If the amount owed is less, it will be added to the earnings of a later block (which may then total over the threshold amount).
If a miner does not submit a share for over a week, the pool sends any balance remaining, regardless of its size.

===P2Pool approach===

[[P2Pool]] mining nodes work on a chain of shares similar to Bitcoin’s blockchain. When a block is found, the reward is divided among the most recent shares in this share-blockchain. Like the puddinpop and Luke-Jr approaches, p2pool pays via generation.

===Comparison===

The cooperative mining approach (slush and Luke-Jr) uses a lot less resources on the pool server, since rather than continuously checking metahashes, all that has to be checked is the validity of submitted shares. The number of shares sent can be adjusted by adjusting the artificial difficulty level.

Further, the cooperative mining approach allows the clients to use existing miners without any modification, while the puddinpop approach requires the custom pool miner, which are as of now not as efficient on GPU mining as the existing GPU miners.
[[File:Smallgeneration.png|thumb|Puddinpop miners receive coins directly.]]

Additionally, the puddinpop and Luke-Jr approaches of distributing the earnings by way of including precise sub-cent amounts in the generation transaction for the participants, results in the presence of sub-cent bitcoin amounts in your wallet, which are liable to disappear (as unnecessary fees) later due to a bug in old (before 0.3.21) bitcoin nodes. (E.g., if you have a transaction with 0.052 in your wallet, and you later send .05 to someone, your .002 will disappear.).

Puddinpop and Luke-Jr miners receive coins directly, which eliminates the delay in receiving earnings that is required on slush-based mining servers. However, using some [[eWallet]] services for generated coin will cause those coins to be lost.

==See Also==

* [[:Category:Miners|Miners]]
* [[Poolservers]]
* [[Comparison of mining pools]]
* [[:Category:Pool Operators|Pool Operators]]
* [[Why a GPU mines faster than a CPU]]
* [[Why pooled mining]]
* [[Mining pool reward FAQ]]

==External links==

* [http://www.bitcoin.org/smf/index.php?topic=1458.0 puddinpop's mining pool thread]
* [http://blockexplorer.com/block/00000000000233334b157d901714baf59e5b9236227b2878844e52244da4195e example puddinpop block]

==References==
<references />

* [https://www.bitcoinmining.com/ Bitcoin Mining]
* [https://www.youtube.com/watch?v=GmOzih6I1zs Video: What is Bitcoin Mining]
* [http://bitcoinminer.com Bitcoin Miner]

[[ru:майнинг в пулах]]
[[Category:Mining]]
{{Pools}}

Mining

2015-12-08T03:31:07Z

Sunnankar: /* See Also */ Typo

[[File:Quick-and-dirty-4x5970-cooling.jpg|thumb|right|A quick and dirty mining rig]]
== Introduction ==
'''Mining''' is the process of adding transaction records to Bitcoin's public ledger of past transactions.
This ledger of past transactions is called the [[block chain]] as it is a chain of [[block|blocks]].
The block chain serves to [[Confirmation|confirm]] transactions to the rest of the network as having taken place.
Bitcoin nodes use the block chain to distinguish legitimate Bitcoin transactions from attempts to re-spend coins that have already been spent elsewhere.

Mining is intentionally designed to be resource-intensive and difficult so that the number of blocks found each day by miners remains steady. Individual [[blocks]] must contain a [[proof of work|proof of work]] to be considered valid. This proof of work is verified by other Bitcoin nodes each time they receive a block. Bitcoin uses the [[hashcash]] proof-of-work function.

The primary purpose of mining is to allow Bitcoin nodes to reach a secure, tamper-resistant consensus.
Mining is also the mechanism used to introduce Bitcoins into the system:
Miners are paid any transaction fees as well as a "subsidy" of newly created coins.
This both serves the purpose of disseminating new coins in a decentralized manner as well as motivating people to provide security for the system.

Bitcoin mining is so called because it resembles the mining of other commodities:
it requires exertion and it slowly makes new currency available at a rate that resembles the rate at which commodities like gold are mined from the ground.

== Difficulty ==
=== The Computationally-Difficult Problem ===
Mining a block is difficult because the SHA-256 hash of a block's header must be lower than or equal to the [[Target|target]] in order for the block to be accepted by the network. This problem can be simplified for explanation purposes: The hash of a block must start with a certain number of zeros. The probability of calculating a hash that starts with many zeros is very low, therefore many attempts must be made. In order to generate a new hash each round, a [[Nonce|nonce]] is incremented. See [[Proof of work]] for more information.

=== The Difficulty Metric ===
The [[Difficulty|difficulty]] is the measure of how difficult it is to find a new block compared to the easiest it can ever be. It is recalculated every 2016 blocks to a value such that the previous 2016 blocks would have been generated in exactly two weeks had everyone been mining at this difficulty. This will yield, on average, one block every ten minutes. As more miners join, the rate of block creation will go up. As the rate of block generation goes up, the difficulty rises to compensate which will push the rate of block creation back down. Any blocks released by malicious miners that do not meet the required difficulty [[Target|target]] will simply be rejected by everyone on the network and thus will be worthless.

=== Reward ===
When a block is discovered, the discoverer may award themselves a certain number of bitcoins, which is agreed-upon by everyone in the network. Currently this bounty is 25 bitcoins; this value will halve every 210,000 blocks. See [[Controlled Currency Supply]].

Additionally, the miner is awarded the fees paid by users sending transactions. The fee is an incentive for the miner to include the transaction in their block. In the future, as the number of new bitcoins miners are allowed to create in each block dwindles, the fees will make up a much more important percentage of mining income.

== The mining ecosystem ==

=== Hardware ===
[[File:Usb-fpga module 1.15x-hs-800.jpg|thumb|right|FPGA Module]]
Users have used various types of hardware over time to mine blocks. Hardware specifications and performance statistics are detailed on the [[Mining Hardware Comparison]] page.
==== CPU Mining ====
Early Bitcoin client versions allowed users to use their CPUs to mine. The advent of GPU mining made CPU mining financially unwise as the hashrate of the network grew to such a degree that the amount of bitcoins produced by CPU mining became lower than the cost of power to operate a CPU. The option was therefore removed from the core Bitcoin client's user interface.

==== GPU Mining ====
GPU Mining is drastically faster and more efficient than CPU mining. See the main article: [[Why a GPU mines faster than a CPU]]. A variety of popular [[Mining rig|mining rigs]] have been documented.
==== FPGA Mining ====
FPGA mining is a very efficient and fast way to mine, comparable to GPU mining and drastically outperforming CPU mining. FPGAs typically consume very small amounts of power with relatively high hash ratings, making them more viable and efficient than GPU mining. See [[Mining Hardware Comparison]] for FPGA hardware specifications and statistics.
==== ASIC Mining ====
An application-specific integrated circuit, or ''ASIC'', is a microchip designed and manufactured for a very specific purpose. ASICs designed for Bitcoin mining were first released in 2013. For the amount of power they consume, they are vastly faster than all previous technologies and already have made GPU mining financially unwise in some countries and setups.

==== Mining services (Cloud mining) ====
[[:Category:Mining_contractors|Mining contractors]] provide mining services with performance specified by contract, often referred to as a "Mining Contract". They may, for example, rent out a specific level of mining capacity for a set price for a specific duration.

=== Pools ===
As more and more miners competed for the limited supply of blocks, individuals found that they were working for months without finding a block and receiving any reward for their mining efforts. This made mining something of a gamble. To address the variance in their income miners started organizing themselves into [[Pooled mining|pools]] so that they could share rewards more evenly. See [[Pooled mining]] and [[Comparison of mining pools]].

=== History ===
Bitcoin's public ledger (the 'block chain') was started on January 3rd, 2009 at 18:15 UTC presumably by [[Satoshi Nakamoto]]. The first block is known as the [[genesis block]]. The first transaction recorded in the first block was a single transaction paying the reward of 50 new bitcoins to its creator.

==See Also==

* [https://www.bitcoinmining.com Bitcoin Mining]
* [http://codinginmysleep.com/bitcoin-mining-in-plain-english Bitcoin Mining in Plain English] by David Perry
* [https://www.weusecoins.com/en/mining-guide/ Getting Started With Bitcoin Mining]
* [[Automatically mine when computer is locked|Tutorial to automatically start mining when you lock your computer]]. (Windows 7)
* [http://bitcoinminer.com Bitcoin Miner]
* [http://www.reddit.com/r/Bitcoin/comments/18q2jx/eli5_bitcoin_mining_xpost_in_eli5/ Simplified Explanation of Bitcoin Mining] by reddit user [http://www.reddit.com/user/azotic azotic]
* [https://bitcoinchain.com/pools Bitcoin Mining Pools Comparison]
* [http://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ Research, Review and Compare Cloud Mining Contracts]
* [https://www.youtube.com/watch?v=GmOzih6I1zs Video: What is Bitcoin Mining?]
* [http://yogh.io/#mine:last Mining Simulator] ([https://github.com/JornC/bitcoin-transaction-explorer GitHub source])
[[ru:Mining]]
[[Category:Mining]][[Category:Vocabulary]]

Mining

2015-12-08T03:30:22Z

Sunnankar: /* See Also */

[[File:Quick-and-dirty-4x5970-cooling.jpg|thumb|right|A quick and dirty mining rig]]
== Introduction ==
'''Mining''' is the process of adding transaction records to Bitcoin's public ledger of past transactions.
This ledger of past transactions is called the [[block chain]] as it is a chain of [[block|blocks]].
The block chain serves to [[Confirmation|confirm]] transactions to the rest of the network as having taken place.
Bitcoin nodes use the block chain to distinguish legitimate Bitcoin transactions from attempts to re-spend coins that have already been spent elsewhere.

Mining is intentionally designed to be resource-intensive and difficult so that the number of blocks found each day by miners remains steady. Individual [[blocks]] must contain a [[proof of work|proof of work]] to be considered valid. This proof of work is verified by other Bitcoin nodes each time they receive a block. Bitcoin uses the [[hashcash]] proof-of-work function.

The primary purpose of mining is to allow Bitcoin nodes to reach a secure, tamper-resistant consensus.
Mining is also the mechanism used to introduce Bitcoins into the system:
Miners are paid any transaction fees as well as a "subsidy" of newly created coins.
This both serves the purpose of disseminating new coins in a decentralized manner as well as motivating people to provide security for the system.

Bitcoin mining is so called because it resembles the mining of other commodities:
it requires exertion and it slowly makes new currency available at a rate that resembles the rate at which commodities like gold are mined from the ground.

== Difficulty ==
=== The Computationally-Difficult Problem ===
Mining a block is difficult because the SHA-256 hash of a block's header must be lower than or equal to the [[Target|target]] in order for the block to be accepted by the network. This problem can be simplified for explanation purposes: The hash of a block must start with a certain number of zeros. The probability of calculating a hash that starts with many zeros is very low, therefore many attempts must be made. In order to generate a new hash each round, a [[Nonce|nonce]] is incremented. See [[Proof of work]] for more information.

=== The Difficulty Metric ===
The [[Difficulty|difficulty]] is the measure of how difficult it is to find a new block compared to the easiest it can ever be. It is recalculated every 2016 blocks to a value such that the previous 2016 blocks would have been generated in exactly two weeks had everyone been mining at this difficulty. This will yield, on average, one block every ten minutes. As more miners join, the rate of block creation will go up. As the rate of block generation goes up, the difficulty rises to compensate which will push the rate of block creation back down. Any blocks released by malicious miners that do not meet the required difficulty [[Target|target]] will simply be rejected by everyone on the network and thus will be worthless.

=== Reward ===
When a block is discovered, the discoverer may award themselves a certain number of bitcoins, which is agreed-upon by everyone in the network. Currently this bounty is 25 bitcoins; this value will halve every 210,000 blocks. See [[Controlled Currency Supply]].

Additionally, the miner is awarded the fees paid by users sending transactions. The fee is an incentive for the miner to include the transaction in their block. In the future, as the number of new bitcoins miners are allowed to create in each block dwindles, the fees will make up a much more important percentage of mining income.

== The mining ecosystem ==

=== Hardware ===
[[File:Usb-fpga module 1.15x-hs-800.jpg|thumb|right|FPGA Module]]
Users have used various types of hardware over time to mine blocks. Hardware specifications and performance statistics are detailed on the [[Mining Hardware Comparison]] page.
==== CPU Mining ====
Early Bitcoin client versions allowed users to use their CPUs to mine. The advent of GPU mining made CPU mining financially unwise as the hashrate of the network grew to such a degree that the amount of bitcoins produced by CPU mining became lower than the cost of power to operate a CPU. The option was therefore removed from the core Bitcoin client's user interface.

==== GPU Mining ====
GPU Mining is drastically faster and more efficient than CPU mining. See the main article: [[Why a GPU mines faster than a CPU]]. A variety of popular [[Mining rig|mining rigs]] have been documented.
==== FPGA Mining ====
FPGA mining is a very efficient and fast way to mine, comparable to GPU mining and drastically outperforming CPU mining. FPGAs typically consume very small amounts of power with relatively high hash ratings, making them more viable and efficient than GPU mining. See [[Mining Hardware Comparison]] for FPGA hardware specifications and statistics.
==== ASIC Mining ====
An application-specific integrated circuit, or ''ASIC'', is a microchip designed and manufactured for a very specific purpose. ASICs designed for Bitcoin mining were first released in 2013. For the amount of power they consume, they are vastly faster than all previous technologies and already have made GPU mining financially unwise in some countries and setups.

==== Mining services (Cloud mining) ====
[[:Category:Mining_contractors|Mining contractors]] provide mining services with performance specified by contract, often referred to as a "Mining Contract". They may, for example, rent out a specific level of mining capacity for a set price for a specific duration.

=== Pools ===
As more and more miners competed for the limited supply of blocks, individuals found that they were working for months without finding a block and receiving any reward for their mining efforts. This made mining something of a gamble. To address the variance in their income miners started organizing themselves into [[Pooled mining|pools]] so that they could share rewards more evenly. See [[Pooled mining]] and [[Comparison of mining pools]].

=== History ===
Bitcoin's public ledger (the 'block chain') was started on January 3rd, 2009 at 18:15 UTC presumably by [[Satoshi Nakamoto]]. The first block is known as the [[genesis block]]. The first transaction recorded in the first block was a single transaction paying the reward of 50 new bitcoins to its creator.

==See Also==

* [https://www.bitcoinmining.com Bitcoin Mining]
* [http://codinginmysleep.com/bitcoin-mining-in-plain-english Bitcoin Mining in Plain English] by David Perry
* [https://www.weusecoins.com/en/mining-guide/ Getting Started With Bitcoin Mining]
* [[Automatically mine when computer is locked|Tutorial to automatically start mining when you lock your computer]]. (Windows 7)
* [https://www.bitcoinminer.com Bitcoin Miner]
* [http://www.reddit.com/r/Bitcoin/comments/18q2jx/eli5_bitcoin_mining_xpost_in_eli5/ Simplified Explanation of Bitcoin Mining] by reddit user [http://www.reddit.com/user/azotic azotic]
* [https://bitcoinchain.com/pools Bitcoin Mining Pools Comparison]
* [http://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ Research, Review and Compare Cloud Mining Contracts]
* [https://www.youtube.com/watch?v=GmOzih6I1zs Video: What is Bitcoin Mining?]
* [http://yogh.io/#mine:last Mining Simulator] ([https://github.com/JornC/bitcoin-transaction-explorer GitHub source])
[[ru:Mining]]
[[Category:Mining]][[Category:Vocabulary]]

Mining

2015-11-30T08:38:49Z

Sunnankar: /* See Also */

[[File:Quick-and-dirty-4x5970-cooling.jpg|thumb|right|A quick and dirty mining rig]]
== Introduction ==
'''Mining''' is the process of adding transaction records to Bitcoin's public ledger of past transactions.
This ledger of past transactions is called the [[block chain]] as it is a chain of [[block|blocks]].
The block chain serves to [[Confirmation|confirm]] transactions to the rest of the network as having taken place.
Bitcoin nodes use the block chain to distinguish legitimate Bitcoin transactions from attempts to re-spend coins that have already been spent elsewhere.

Mining is intentionally designed to be resource-intensive and difficult so that the number of blocks found each day by miners remains steady. Individual [[blocks]] must contain a [[proof of work|proof of work]] to be considered valid. This proof of work is verified by other Bitcoin nodes each time they receive a block. Bitcoin uses the [[hashcash]] proof-of-work function.

The primary purpose of mining is to allow Bitcoin nodes to reach a secure, tamper-resistant consensus.
Mining is also the mechanism used to introduce Bitcoins into the system:
Miners are paid any transaction fees as well as a "subsidy" of newly created coins.
This both serves the purpose of disseminating new coins in a decentralized manner as well as motivating people to provide security for the system.

Bitcoin mining is so called because it resembles the mining of other commodities:
it requires exertion and it slowly makes new currency available at a rate that resembles the rate at which commodities like gold are mined from the ground.

== Difficulty ==
=== The Computationally-Difficult Problem ===
Mining a block is difficult because the SHA-256 hash of a block's header must be lower than or equal to the [[Target|target]] in order for the block to be accepted by the network. This problem can be simplified for explanation purposes: The hash of a block must start with a certain number of zeros. The probability of calculating a hash that starts with many zeros is very low, therefore many attempts must be made. In order to generate a new hash each round, a [[Nonce|nonce]] is incremented. See [[Proof of work]] for more information.

=== The Difficulty Metric ===
The [[Difficulty|difficulty]] is the measure of how difficult it is to find a new block compared to the easiest it can ever be. It is recalculated every 2016 blocks to a value such that the previous 2016 blocks would have been generated in exactly two weeks had everyone been mining at this difficulty. This will yield, on average, one block every ten minutes. As more miners join, the rate of block creation will go up. As the rate of block generation goes up, the difficulty rises to compensate which will push the rate of block creation back down. Any blocks released by malicious miners that do not meet the required difficulty [[Target|target]] will simply be rejected by everyone on the network and thus will be worthless.

=== Reward ===
When a block is discovered, the discoverer may award themselves a certain number of bitcoins, which is agreed-upon by everyone in the network. Currently this bounty is 25 bitcoins; this value will halve every 210,000 blocks. See [[Controlled Currency Supply]].

Additionally, the miner is awarded the fees paid by users sending transactions. The fee is an incentive for the miner to include the transaction in their block. In the future, as the number of new bitcoins miners are allowed to create in each block dwindles, the fees will make up a much more important percentage of mining income.

== The mining ecosystem ==

=== Hardware ===
[[File:Usb-fpga module 1.15x-hs-800.jpg|thumb|right|FPGA Module]]
Users have used various types of hardware over time to mine blocks. Hardware specifications and performance statistics are detailed on the [[Mining Hardware Comparison]] page.
==== CPU Mining ====
Early Bitcoin client versions allowed users to use their CPUs to mine. The advent of GPU mining made CPU mining financially unwise as the hashrate of the network grew to such a degree that the amount of bitcoins produced by CPU mining became lower than the cost of power to operate a CPU. The option was therefore removed from the core Bitcoin client's user interface.

==== GPU Mining ====
GPU Mining is drastically faster and more efficient than CPU mining. See the main article: [[Why a GPU mines faster than a CPU]]. A variety of popular [[Mining rig|mining rigs]] have been documented.
==== FPGA Mining ====
FPGA mining is a very efficient and fast way to mine, comparable to GPU mining and drastically outperforming CPU mining. FPGAs typically consume very small amounts of power with relatively high hash ratings, making them more viable and efficient than GPU mining. See [[Mining Hardware Comparison]] for FPGA hardware specifications and statistics.
==== ASIC Mining ====
An application-specific integrated circuit, or ''ASIC'', is a microchip designed and manufactured for a very specific purpose. ASICs designed for Bitcoin mining were first released in 2013. For the amount of power they consume, they are vastly faster than all previous technologies and already have made GPU mining financially unwise in some countries and setups.

==== Mining services (Cloud mining) ====
[[:Category:Mining_contractors|Mining contractors]] provide mining services with performance specified by contract, often referred to as a "Mining Contract". They may, for example, rent out a specific level of mining capacity for a set price for a specific duration.

=== Pools ===
As more and more miners competed for the limited supply of blocks, individuals found that they were working for months without finding a block and receiving any reward for their mining efforts. This made mining something of a gamble. To address the variance in their income miners started organizing themselves into [[Pooled mining|pools]] so that they could share rewards more evenly. See [[Pooled mining]] and [[Comparison of mining pools]].

=== History ===
Bitcoin's public ledger (the 'block chain') was started on January 3rd, 2009 at 18:15 UTC presumably by [[Satoshi Nakamoto]]. The first block is known as the [[genesis block]]. The first transaction recorded in the first block was a single transaction paying the reward of 50 new bitcoins to its creator.

==See Also==

* [https://www.bitcoinmining.com Bitcoin Mining]
* [http://codinginmysleep.com/bitcoin-mining-in-plain-english Bitcoin Mining in Plain English] by David Perry
* [https://www.weusecoins.com/en/mining-guide/ Getting Started With Bitcoin Mining]
* [[Automatically mine when computer is locked|Tutorial to automatically start mining when you lock your computer]]. (Windows 7)
* [http://www.reddit.com/r/Bitcoin/comments/18q2jx/eli5_bitcoin_mining_xpost_in_eli5/ Simplified Explanation of Bitcoin Mining] by reddit user [http://www.reddit.com/user/azotic azotic]
* [https://bitcoinchain.com/pools Bitcoin Mining Pools Comparison]
* [http://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ Research, Review and Compare Cloud Mining Contracts]
* [https://www.youtube.com/watch?v=GmOzih6I1zs Video: What is Bitcoin Mining?]
* [http://yogh.io/#mine:last Mining Simulator] ([https://github.com/JornC/bitcoin-transaction-explorer GitHub source])
[[ru:Mining]]
[[Category:Mining]][[Category:Vocabulary]]

Coinbase (business)

2015-08-28T17:18:09Z

Sunnankar: /* References */

:''Not to be confused with the transaction [[coinbase]].''
{{infobox company|name=Coinbase, Inc.|image=[[File:Coinbase.png]]
|industry=[[eWallet]], [[exchange]]
|founder=[[Brian Armstrong]], [[Fred Ehrsam]]
|foundation=June 20, 2012
|location=San Francisco, CA, United States
|assets={{increase}} 366,492 BTC (2015) / {{increase}} $105 million USD (2015)
|twitter=coinbase
|facebook=Coinbase
|
|website=[https://www.coinbase.com/ coinbase.com]}}'''Coinbase''' is a hosted web-based [[eWallet]] used for sending, receiving, and storing bitcoins. Users can also connect a U.S. based bank account to buy and sell bitcoin via bank transfer.

The service aims to be the easiest way to get started with Bitcoin, modeled to provide an experience familiar to those who are comfortable using PayPal.

==Transactions==

===Buy Bitcoin===

Coinbase allows users to purchase bitcoin by directly transferring money from a bank account. Although the exchange rate is locked in at the time of order placement, the Bitcoin is not released for four business days. Verified users are allowed to create instant-purchases, which credits the Bitcoin to their account before the bank transfer clears.

Linking a bank account can be done using Instant Account Verification (by providing your bank account credentials) or through a Challenge Deposit method which takes 2-3 business days to complete. The bank verification process is very similar to the relevant procedure at PayPal.

===Sell Bitcoin===

Proceeds from selling bitcoins are sent as a direct ACH transfer to a linked bank account. The price is locked upon executing the sell and the funds arrive in the bank account in 2-3 business days.

===Send Money===

This feature provides the ability to send bitcoin to both email and Bitcoin addresses. The amount of bitcoin sent can be determined by entering a value in either USD (converted to Bitcoin based on the current exchange rate) or Bitcoin. If bitcoin is sent to an email address not currently registered with Coinbase, an account will automatically be created and a message will be sent to that email address prompting the user to verify the account and claim the bitcoin.

===Request Money===

This feature provides the ability to request funds (denominated in either USD or BTC) through an invoice which is sent by email.

===Exchange===

On January 26, 2015 Coinbase announced via a blog post <ref>[http://blog.coinbase.com/post/109202118547/coinbase-launches-first-regulated-bitcoin-exchange Coinbase Launches First Regulated Bitcoin Exchange in the U.S.]</ref> they were launching a United States based and US regulated bitcoin exchange. The exchange located at [https://exchange.coinbase.com/ https://exchange.coinbase.com/] allows users from select US states and territories begin trading using an order book on the Coinbase website.

==Merchant Tools==

[https://developers.coinbase.com/docs/merchants/payment-buttons Payment buttons] make it easy to accept bitcoin on any website by copying and pasting a few lines of code.

[https://developers.coinbase.com/docs/merchants/payment-pages Payment pages] allow merchants to accept bitcoin with a hosted checkout page on coinbase.com.

[https://developers.coinbase.com/docs/merchants/callbacks Callbacks] allow for instant payment notifications to a merchant's website.

[https://developers.coinbase.com/docs/merchants/payouts Payouts] allow merchants to cash out bitcoin on a daily basis through a USD transfer to a linked bank account without exchange rate risk.

Coinbase also offers an [https://developers.coinbase.com/docs/wallet API] for custom applications or merchant integrations.

==Fees==

There are no fees for sending, receiving, or storing bitcoin.

The fee for buying or selling bitcoin with a bank transfer is a fixed 1% + $0.15. This fee is waived on automatic sell orders made using their merchant instant-exchange functionality.

==History==

The service was announced on June 29, 2012 and received seed funding from Paul Graham after going through the startup incubator Y-Combinator<ref>[http://bitcointalk.org/index.php?topic=90779.0 Coinbase - Funded by Paul Graham]</ref>.

On October 26, 2012, the service launched its method to buy and sell bitcoins using a linked bank account<ref>[http://blog.coinbase.com/post/34357253898/you-can-now-buy-and-sell-bitcoin-by-connecting-any-u-s You Can Now Buy And Sell Bitcoin By Connecting Any U.S. Bank Account]</ref>.

On December 5, 2012, Coinbase launched its Merchant Tools<ref>[http://coinbase.com/post/37274999622/how-to-accept-bitcoin-on-your-website How To Accept Bitcoin On Your Website]</ref>.

On May 7, 2013, Coinbase announced that it had received five million dollars in funding led by the venture capital firm Union Square Ventures. It was the largest funding round to date for a bitcoin company<ref>[http://blogs.wsj.com/venturecapital/2013/05/07/coinbase-nabs-5m-in-biggest-funding-for-bitcoin-startup/ Coinbase Nabs $5M in Biggest Funding for Bitcoin Startup]</ref>.

On July 11, 2013, Coinbase launched instant buys for fully verified users<ref>[http://blog.coinbase.com/post/55203204550/instant-bitcoin-purchases-at-coinbase Instant Bitcoin Purchases at Coinbase]</ref>.

On December 12, 2013, Coinbase announced Series B funding of $25 million dollars led by the venture capital firm Andreessen Horowitz. It is the largest round of funding received by a bitcoin company<ref>[http://www.forbes.com/sites/kashmirhill/2013/12/12/bitcoin-wallet-coinbase-deposits-25-million-from-andreessen-horowitz/ Bitcoin's Biggest Investment]</ref>.

On February 27th, 2014, Coinbase announced that 1 Million consumer wallet accounts have been opened on their platform <ref>[http://blog.coinbase.com/post/78016535692/a-major-coinbase-milestone-1-million-consumer-wallets 1 Million Consumer Wallets]</ref>.

On May 7th, 2014, Coinbase announced that they acquired the content-sharing platform Kippt. <ref>[http://www.coindesk.com/coinbase-boosts-team-acquisition-kippt-developers/ Coinbase Boosts Team with Acquisition of Kippt Developers]</ref>

On August 18th, 2014, Coinbase announced that they acquired the block explorer company Blockr.io. <ref>[http://techcrunch.com/2014/08/18/coinbase-acquires-blockchain-explore-blockr-io/ Coinbase Acquires Blockchain Explorer Blockr.io]</ref>

==See Also==

* [[Buying bitcoins]]
* [[Selling bitcoins]]

==External Links==

* [http://www.Coinbase.com Coinbase.com] website

==References==
<references/>

[[Category:EWallets]]
[[Category:Wallets]]
[[Category:Exchanges]]
[[Category:Shopping Cart Interfaces]]
[[Category:Services]]
[[Category:Frontends]]
[[Category:Clients]]
[[Category:Mobile]]

[https://www.weusecoins.com/coinbase-review/ Coinbase Review]

Mining hardware comparison

2015-08-04T14:40:40Z

Sunnankar: /* FPGA */

{{seealso|Non-specialized hardware comparison}}
Below are statistics about the Bitcoin [[Mining]] performance of [[ASIC]] hardware and '''only includes specialized equipment that has been shipped.'''

GPUs, CPUs and other hardware not specifically designed for Bitcoin mining can be found in the [[Non-specialized_hardware_comparison]].

'''Notes:'''
* Mhash/s = millions [[hash per second|hashes per second]] ([[Protocol_specification#Hashes|double sha256]] raw speed performance; may not be very energy efficient with some models)
* Mhash/J = millions hashes per joule (energy efficiency; 1 joule of energy is 1 watt during 1 second: 1 J = 1 W*s)
* W = watt (maximum power consumption, i.e. energy per unit of time: 1 W = 1 J/s)

== ASIC ==

'''Be sure to research any of these vendors and machines intensely before spending any money.'''

{| class="wikitable sortable"
|+ Bitcoin [[Protocol_specification#Hashes|double SHA256]] ASIC mining hardware
! data-sort-type="text" | Product !! data-sort-type="number" | Advertised Mhash/s !! data-sort-type="number" | Mhash/J !! data-sort-type="number" | Mhash/s/$ !! data-sort-type="number" | Watts !! data-sort-type="currency" | Price (USD) !! data-sort-type="date" | Currently shipping !! class="unsortable" | Comm ports !! class="unsortable" | Dev-friendly
|-
! [[AntMiner]] S1 <ref name="AntMinerS1"/>
| 180,000 || 500 || 800|| 360 || 299<ref name="nopsu">Power supply not included</ref> || {{No|Discontinued}} || Ethernet || {{No|GPL infringement}}
|-
! [[AntMiner]] S2 <ref name="AntMinerS2"/>
| 1,000,000 || 900|| 442|| 1100|| 2259|| {{No|Discontinued}} || Ethernet || {{No|GPL infringement}}
|-
! [[AntMiner]] S3 <ref name="AntMinerS3">[https://bitmaintech.com/productDetail.htm?pid=00020140917060843699l3bEXYxL06C0 Ant Miner S3 product page] Retrieved 2014-08-06</ref>
| 441,000 || 1300|| 1154|| 340|| 382<ref name="nopsu"/> || {{No|Discontinued}} || Ethernet || {{No|GPL infringement}}
|-
! [[AntMiner]] S4 <ref name="AntMinerS4">[https://www.bitmaintech.com/productDetail.htm?pid=00020140926075515819D846Og240603 Ant Miner S4 product page] Retrieved 2014-10-01</ref>
| 2,000,000 || 1429|| 1429 || 1400 || 1400 || {{No|Discontinued}} || Ethernet || {{No|GPL infringement}}
|-
! [[AntMiner]] S5 <ref name="AntMinerS5">[https://www.bitmaintech.com/productDetail.htm?pid=000201412231604153619o9X1obn0693 Ant Miner S5 product page] Retrieved 2015-02-04</ref>
| 1,155,000 || 1957 || 3121 || 590 || 370 || {{Yes}} || Ethernet || {{No|GPL infringement}}
|-
! [[AntMiner]] U1 <ref name="AntMinerU1"/>
| 1,600 || 800 || 55 || 2 || 29 || {{No|Discontinued}} || USB || {{Yes|code, samples}}
|-
! [[AntMiner]] U2+ <ref name="AntMinerU2"/>
| 2,000 || 1,000 || 115 || 2 || 17 || {{No|Discontinued}} || USB || {{No|code}}
|-
! [[AntMiner]] U3 <ref name="AntMinerU3">[https://www.bitmaintech.com/productDetail.htm?pid=00020150109104550452NTD3NdYY0669 Antminer U3 product page] Retrieved 2015-02-06</ref>
| 63,000 || 1,000 || 1658 || 63 || 38 || {{Yes}} || USB || {{No|code}}
|-
! [[ASICMiner]] BE Blade
| 10,752 || 129 || 28<ref name="bcprice"/> || 83 || 350<ref name="nopsu"/><ref name="bcprice"/> || {{No|Discontinued}} || Ethernet || {{Patch|samples}}
|-
! [[ASICMiner]] BE Cube
| 30,000 || 150 || 55 || 200 || 550<ref name="nopsu"/><ref name="bcprice"/> || {{No|Discontinued}} || Ethernet || {{Patch|samples}}
|-
! [[ASICMiner]] BE Sapphire
| 336 || 130 || 17<ref name="bcprice"/> || 2.55 || 20<ref name="bcprice">Actual price is in bitcoins. USD value estimated.</ref> || {{No|Discontinued}} || USB || {{Yes|samples}}
|-
! [[ASICMiner]] BE Tube <ref name="AM tube">[https://bitcointalk.org/index.php?topic=735728.0 ASICMiner Tube Sales Thread]</ref>
| 800,000 || 888 || 2500 || 900 || 320<ref name="nopsu"/> || {{No|Discontinued}} || Proprietary || {{Patch|samples}}
|-
! [[ASICMiner]] BE Prisma <ref name="AM prisma">[https://bitcointalk.org/index.php?topic=791827.0 ASICMiner Prisma Sales Thread]</ref>
| 1,400,000 || 1333 || 2333 || 1100 || 600<ref name="nopsu"/> || {{No|Discontinued}} || Proprietary || {{No}}
|-
! [[Avalon]] Batch 1
| 66,300 <ref name="AvalonPowerUsage"/> || 107 || 52.34 || 620<ref name="AvalonPowerUsage"/> || 1299<ref name="avalon"/> || {{No|Discontinued}} || Ethernet, Wifi || {{No|code}}
|-
! [[Avalon]] Batch 2
| 82,000<ref name="avalon" /> || 117 || 54.70 || 700 || 1499<ref name="avalon" /> || {{No|Discontinued}} || Ethernet, Wifi || {{No|code}}
|-
! [[Avalon]] Batch 3
| 82,000<ref name="avalon" /> || 117 || 54.70 || 700 || 1499<ref name="avalon" /> || {{No|Discontinued}} || Ethernet, Wifi || {{No|code}}
|-
! [[Avalon2]]
| 300,000 || {{Patch|}} || {{Patch|}} || {{Patch|}} || 3075 || {{No|Discontinued}} || USB or Ethernet || {{Yes|code, docs, samples}}
|-
! [[Avalon3]]
| 800,000 || {{Patch|}} || {{Patch|}} || {{Patch|}} || {{Patch|}} || {{No|Discontinued}} || USB or Ethernet || {{Yes|code, docs, samples}}
|-
! bi*fury
| 5,000 || 1,176 || 24 || 4.25 || 209 || {{No|Discontinued}} || USB || {{Yes|docs, samples}}
|-
! BFL SC 5Gh/s
| 5,000 || 166 || 18.24 || 30 || 274 || {{No|Discontinued}} || USB || {{Yes|docs, samples}}
|-
! BFL SC 10 Gh/s
| 10,000 || {{Patch|}} || 200 || {{Patch|}} || 50 || {{Yes}} || USB || {{Yes|docs, samples}}
|-
! BFL SC 25 Gh/s
| 25,000 || 166 || 20.00 || 150 || 1249 || {{No|Discontinued}} || USB || {{Yes|docs, samples}}
|-
! BFL Little Single
| 30,000 || {{Patch|}} || 46.22 || {{Patch|}} || 649 || {{No|Discontinued}} || USB || {{Yes|docs, samples}}
|-
! BFL SC 50 Gh/s
| 50,000 || 166 || 50 || 300|| 984 || {{No|Discontinued}} || USB || {{Yes|docs, samples}}
|-
! BFL Single 'SC'
| 60,000 || 250 || 46.18 || 240 || 1299 || {{No|Discontinued}} || USB || {{Yes|docs, samples}}
|-
! BFL 230 GH/s Rack Mount<ref name="bf250">[https://products.butterflylabs.com/homepage-new-products/250-gh-s-rack-mount-bitcoin-miner.html "250 GH/s Rack Mount Bitcoin Miner"]. Butterfly Labs. Retrieved September 2, 2014.</ref>
| 230,000 || {{Patch|}} || 500|| {{Patch|}} || 399 (used) || {{No|Discontinued}} || USB || {{Patch|docs}}
|-
! BFL 500 GH/s Mini Rig SC
| 500,000 || 185 || {{Patch|}} || 2700 || 22484 || {{No|Discontinued}} || Wifi || {{Yes|docs, samples}}
|-
! BFL Monarch 700GH/s<ref name="bflmonarch">[https://products.butterflylabs.com/homepage-new-products/700-gh-bitcoin-mining-card.html "700GH/s Bitcoin Mining Card"]. Butterfly Labs. Retrieved September 25, 2014.</ref>
| 700,000 || 1428 || 508 || 490 || 1379 || {{Yes}} || PCIe, USB || {{Yes|docs, samples}}

|-
! BitFury S.B.
| {{Patch|}} || {{Patch|}} || {{Patch|}} || {{Patch|}} || {{Patch|}} || {{No|Discontinued}} || RPi GPIO || {{No}}
|-
! Bitmine.ch Avalon Clone 85GH
| 85,000 || {{Patch|}} || 13 || 650 || 6489<ref>Depends on user configuration available from http://www.bitmine.ch</ref> || {{No|Discontinued}} || Ethernet, Wifi, USB || {{No|code}}
|-
! Black Arrow Prospero X-1
| 100,000 || 1000 || 270 || 100 || 370 || {{No|Discontinued}} || Ethernet || {{Patch|docs, samples}}
|-
! Black Arrow Prospero X-3
| 2,000,000 || 1000 || 333 || 2000 || 6000 || {{No|Discontinued}} || Ethernet || {{Patch|?}}
|-
! Blue Fury
| 2,500 || 1000 || 17.8 || 2.5 || 140 || {{No|Discontinued}} || USB || {{Yes|code, samples}}
|-
! BTC Garden AM-V1 310 GH/s<ref name="btcgarden">[https://bitcointalk.org/index.php?topic=622439.0 "BTCGarden Sales Thread"]</ref>
| 310,000 || 954 || 1003 || 324 || 309<ref name="nopsu"/> || {{No|Discontinued}} || RPi GPIO || {{No}}
|-
! BTC Garden AM-V1 616 GH/s<ref name="btcgarden" />
| 616,000 || 951 || 1760 || 648 || 350<ref name="nopsu"/> || {{No|Discontinued}} || RPi GPIO || {{No}}
|-
! [[CoinTerra]] TerraMiner IV
| 1,600,000 || {{Patch|}} || 1066.67 || 2100 || 1500 || {{No|Discontinued}} || Ethernet || {{Yes|docs, code, samples}}
|-
! Drillbit
| {{Patch|}} || {{Patch|}} || {{Patch|}} || {{Patch|}} || {{Patch|}} || {{No|Discontinued}} || USB || {{Yes|code, samples}}
|-
! HashBuster Micro
| 20,000 || 869 || 29 || 23 || 688 || {{No|Discontinued}} || USB || {{Yes|docs, samples}}
|-
! HashBuster Nano
| {{Patch|}} || {{Patch|}} || {{Patch|}} || {{Patch|}} || {{Patch|}} || {{No|Discontinued}} || USB || {{Yes|docs, samples}}
|-
! [[HashCoins]] Apollo v3
| 1100,000<ref name="HCA">[https://www.hashcoins.com/buy-asic-miners/buy-apollo/ "HashCoins Apollo v3"]. HashCoins.</ref> || xxxx || {{Patch|}} || 1000<ref name="HCA"/> || 599<ref name="HCA"/> || {{No|Discontinued}} || USB || {{No}}
|-
! [[HashCoins]] Zeus v3
| 4,500,000<ref name="HCZ">[https://www.hashcoins.com/buy-asic-miners/buy-zeus/ "HashCoins Zeus v3"]. HashCoins.</ref> || xxxx || {{Patch|}} || 3000<ref name="HCZ"/> || 2299<ref name="HCZ"/> || {{No|Discontinued}} || USB || {{No}}
|-
! HashFast Baby Jet
| 400,000 || 909 || 71 || 440 || 5600 || {{No|Discontinued}} || Ethernet, USB || {{Patch|docs}}
|-
! HashFast Sierra
| 1,200,000 || 909 || 169 || 1320 || 7080 || {{No|Discontinued}} || USB || {{Yes|docs, samples}}
|-
! HashFast Sierra Evo 3
| 2,000,000 || 909 || 294 || 2200 || 6800 || {{No|Discontinued}} || USB || {{Patch|docs}}
|-
! Klondike
| 5,200 || 160 || 260 || 32 || 20 || {{No|Discontinued}} || USB || {{Patch|samples}}
|-
! [[KnCMiner]] Mercury
| 100,000 || {{Patch|}} || 50.04 || 250 || 1995 || {{No|Discontinued}} || Ethernet || {{Yes|code, samples}}
|-
! KnC Saturn
| 250,000 || 400|| 66 || 300<ref name="nopsu"/> || 2995 || {{No|Discontinued}} || Ethernet || {{Yes|code, samples}}
|-
! KnC Jupiter
| 500,000 || 400|| 80 || 600<ref name="nopsu"/> || 4995 || {{No|Discontinued}} || Ethernet || {{Yes|code, samples}}
|-
! KnC Neptune <ref name="KnC Neptune">[https://www.kncminer.com/categories/miners "KnC Neptunes 3TH first ever 20nm Chip"] KNC Miner</ref>
| 3,000,000 || 1429 || 231 || 2100 || 12995 <ref name="KnC Neptune">[https://www.kncminer.com/products/neptune "Neptune Online Store"] KnC Miner</ref>|| {{No|Discontinued}} || Ethernet || {{Yes|code, samples}}
|-
! LittleFury
| {{Patch|}} || {{Patch|}} || {{Patch|}} || {{Patch|}} || {{Patch|}} || {{No|Discontinued}} || USB || {{Yes|docs, samples}}
|-
! Metabank
| 120,000 || 705 || 56 || 170 || 2160<ref>Actual costs higher outside Russia</ref> || {{No}} || {{Patch|}} || {{Yes|code, samples}}
|-
! NanoFury / IceFury
| 2,000 || 800 || {{Patch|}} || 2.5 || {{Patch|}} || {{No|Discontinued}} || USB || {{Yes|code, docs, samples}}
|-
! NanoFury NF2
| 3,700 || 740 || 74 || 5 || 50 || {{No|Discontinued}} || USB || {{Yes|code, docs, samples}}
|-
! Red/BlueFury
| 2,600 || 1040 || 4 || 2.5 || 640 || {{No|Discontinued}} || USB || {{Yes|code, samples}}
|-
! ROCKMINER R3-BOX<ref name="rockminer">[http://shop.rockminer.com/ "Rockminer Store"]</ref>
| 450,000 || 1000 || 2250 || 450 || 200<ref name="nopsu"/> || {{No|Discontinued}} || USB || {{Yes|code, samples}}
|-
! ROCKMINER R4-BOX<ref name="rockminer" />
| 470,000 || 1000 || 2238 || 470 || 210<ref name="nopsu"/> || {{No|Discontinued}} || USB || {{Yes|code, samples}}
|-
! ROCKMINER Rocket BOX <ref name="rockminer" />
| 450,000 || 937|| 750 || 480 || 599<ref name="nopsu"/> || {{No|Discontinued}} || RPi GPIO || {{Patch|}}
|-
! ROCKMINER R-BOX<ref name="rockminer" />
| 32,000 || 711 || 500 || 45 || 65<ref name="nopsu"/> || {{No|Discontinued}} || USB || {{Yes|code, samples}}
|-
! ROCKMINER R-BOX 110G<ref name="rockminer" />
| 110,000 || 917 || 1250 || 120 || 88<ref name="nopsu"/> || {{No|Discontinued}} || USB || {{Yes|code, samples}}
|-
! ROCKMINER T1 800G<ref name="rockminer" />
| 800,000 || 800 || 2462 || 1000 || 325<ref name="nopsu"/> || {{No|Discontinued}} || USB || {{Yes|code, samples}}
|-
! Spondooliestech SP10 Dawson<ref name="SP10">[http://www.spondoolies-tech.com/products/sp10-dawson-mid-june-batch "SP10 Dawson June Batch"].</ref>
| 1,400,000 || 1120 || 492 || 1250 || 2845 || {{No|Discontinued}} || Ethernet || {{Yes|code, samples}}
|-
! Spondooliestech SP20 Jackson<ref name="SP20">[http://www.spondoolies-tech.com/products/holiday-special-sp20-jackson-shipping-from-stock "SP20 Jackson"] Retrieved 2015-02-06</ref>
| 1,700,000 || 1545 || 1299 || 1100 || 1309<ref name="nopsu"/> || {{No|Discontinued}} || Ethernet || {{Yes|code, samples}}
|-
! Spondooliestech SP30 Yukon<ref name="SP30 Yukon">[http://www.spondoolies-tech.com/products/sp30-yukon-september-batch-1 "SP30 Yukon September Batch 1"].</ref>
| 4,500,000 || 1500 || 1068 || 3000 || 4121 || {{No|Discontinued}} || Ethernet || {{Yes|code, samples}}
|-
! Spondooliestech SP31 Yukon<ref name="SP31 Yukon">[http://www.spondoolies-tech.com/products/sp31-yukon-shipping-from-stock "SP31 Yukon"] Retrieved 2015-02-06</ref>
| 4,900,000 || 1633 || 2361 || 3000 || 2075 || {{No|Discontinued}} || Ethernet || {{Patch|code}}
|-
! Spondooliestech SP35 Yukon<ref name="SP35 Yukon">[http://www.spondoolies-tech.com/products/sp35-yukon-power-shipping-from-stock "SP35 Yukon"] Retrieved 2015-02-06</ref>
| 5,500,000 || 1506 || 2460 || 3650 || 2235 || {{No|Discontinued}} || Ethernet || {{Patch|code}}
|-
! TerraHash Klondike 16 <ref name="Klondike16">[https://terrahash.com/product/4-5-ghsec-module/ "4.5 GH/sec Modular Board (Klondike 16)"].</ref>
| 4,500 || 140 || 18 || 32|| 250 || {{No}} || USB || {{Patch|samples}}
|-
! TerraHash Klondike 64 <ref name="Klondike64">[https://terrahash.com/product/18-ghsec-modular-board/ "18 GH/sec Modular board (Klondike 64)"].</ref>
| 18,000 || 140 || 20 || 127 || 900 || {{No}} || USB || {{Patch|samples}}
|-
! TerraHash DX Mini (full)
| 90,000 || 140 || 15 || 640 || 6000 || {{No}} || USB || {{Patch|}}
|-
! TerraHash DX Large (full)
| 180,000 || 140 || 17.14 || 1,280 || 10500 || {{No}} || USB || {{Patch|}}
|-
! Twinfury
| 4,500 || 1174 || 20 || 3.83 || 216 || {{No|Discontinued}} || USB || {{Yes|code, samples}}
|-

|}
<references>
<ref name="AntMinerS1">[https://www.bitmaintech.com/productDetail.htm?pid=00020140107162747992Ce5uBuxW06D6 Ant Miner S1 product page] Retrieved 2014-03-11</ref>
<ref name="AntMinerS2">[https://www.bitmaintech.com/productDetail.htm?pid=00020140429083756017VwGm90Xx06B5 Ant Miner S2 product page] Retrieved 2014-05-24</ref>

<ref name="AntMinerU1">[https://www.bitmaintech.com/productDetail.htm?pid=000201401071629535717ycyGoWo06FE Ant Miner U1 Product page] Retrieved 2014-03-11</ref>
<ref name="AntMinerU2">[https://www.bitmaintech.com/productDetail.htm?pid=00020140227111546291QgbvQbVr06FB Ant Miner U2+ Product page] Retrieved 2014-03-11</ref>
<ref name="AvalonPowerUsage">http://garzikrants.blogspot.com/2013/02/avalon-miner-power-usage.html</ref>
<ref name="avalon">[http://avalon-asics.com/ "Avalon ASIC"]. Avalon. Retrieved January 30, 2013.</ref>
</references>

== FPGA ==

{| class="wikitable sortable" style="text-align:center"
|-
! Product !! Hash rate [Mhash/s] !! Efficiency [Mhash/J] !! Efficiency [Mhash/s/$] !! Power [W] !! Price [$]
|-
! Avnet Spartan-6 LX150T Development Kit
| 100<ref>Fpgaminer (May 19, 2011). [https://bitcointalk.org/index.php?topic=9047.0 "Official Open Source FPGA Bitcoin Miner"]. Bitcointalk.org. Retrieved February 7, 2013.</ref> || || 0.10 || || 995<ref>[http://avnetexpress.avnet.com/store/em/EMController?action=products&catalogId=500201&storeId=500201&N=0&langId=-1&slnk=b&term=AES-S6DEV-LX150T-G&hrf=http%3A%2F%2Fwww.em.avnet.com%2Fen-us%2Fdesign%2Fdrc%2FPages%2FXilinx-Spartan-6-FPGA-LX150T-Development-Kit.aspx&intcmp=EMA-BUY-AES-S6DEV-LX150T-G "AES-S6DEV-LX150T-G Parts"]. Avnet Express. Retrieved February 7, 2013.</ref>
|-
! Bitcoin Dominator X5000
| 100<ref name="bd" /> || 14.7 || 0.22 || 6.8<ref name="bd" /> || 440<ref name="bd">NewMeat1 (August 18, 2011). [https://bitcointalk.org/index.php?topic=37904.0 "Custom FPGA Board for Sale!"]. Bitcointalk.org. Retrieved January 30, 2013.</ref>
|-
! BitForce SHA256 Single
| 832<ref name="single">[http://www.butterflylabs.com/product-details/ "BitForce SHA256 Single – Technical Specifications"]. Butterfly Labs. Retrieved January 30, 2013.</ref> || 10.4 || 1.38 || 80<ref name="single" /> || 599<ref name="single" />
|-
! Butterflylabs Mini Rig
| 25,200<ref name="mini">[http://web.archive.org/web/20120514032732/http://www.butterflylabs.com/products "Products"]. Butterfly Labs. Archived from the original on May 14, 2012. Retrieved February 7, 2013.</ref> || 20.16 || 1.64 || 1,250<ref name="mini" /> || 15,295<ref name="mini2">[http://www.butterflylabs.com/order-form-bitforce-sha256-mini-rig/ "Order Form – BitForce SHA256 – Mini Rig"]. Butterfly Labs. Retrieved January 30, 2013.</ref>
|-
! Digilent Nexys 2 500K
| 5<ref>The Seven (June 3, 2011). [https://bitcointalk.org/index.php?topic=9047.msg164438#msg164438 "Re: Official Open Source FPGA Bitcoin Miner (Smaller Devices Now Supported!)"]. Bitcointalk.org. Retrieved February 7, 2013.</ref> || || 0.03 || || 149<ref name="dig">[http://www.digilentinc.com/Products/Detail.cfm?Prod=NEXYS2 "Nexys™2 Spartan-3E FPGA Board"]. Digilent. Retrieved January 30, 2013.</ref>
|-
! Icarus
| 380<ref name="ica">Nzghang (November 9, 2011). [https://bitcointalk.org/index.php?topic=51371.0 "FPGA development board 'Icarus' – DisContinued/ important announcement"]. Bitcointalk.org. Retrieved January 30, 2013.</ref> || 19.79 || 0.66 || 19.2<ref name="ica" /> || 569<ref name="ica" />
|-
! KnCMiner Mars
| 6,000 || ??? || 2.15 || ??? || 2,795
|-
! Lancelot<ref name="lan">Nzghang (May 6, 2012). [https://bitcointalk.org/index.php?topic=79835.0 "FPGA development board "Lancelot" - accept bitsteam developer's orders."]. Bitcointalk.org. Retrieved January 30, 2013.</ref>
| 400<ref name="lan1">Black Arrow (Jun 11, 2013). [https://www.cardreaderfactory.com/shop/lancelot.html "Lancelot - Heavy Duty Dual Spartan6 Bitcoin Mining Device"]. cardreaderfactory.com. Retrieved Jun 11, 2013.</ref> || || || 26 || 350<ref name="lan1">Black Arrow (Jun 11, 2013). [https://www.cardreaderfactory.com/shop/lancelot.html "Lancelot - Heavy Duty Dual Spartan6 Bitcoin Mining Device"]. cardreaderfactory.com. Retrieved Jun 11, 2013.</ref>
|-
! ModMiner Quad
| 800<ref name="mmq">[http://www.btcfpga.com/index.php?route=product/product&product_id=50 "ModMiner Quad"]. BTCFPGA. Retrieved January 30, 2013.</ref> || 20 || 0.75 || 40<ref name="mmq" /> || 1,069<ref name="mmq" />
|-
! Terasic DE2-115
| 80<ref>Fpgaminer (May 4, 2011). [https://bitcointalk.org/index.php?topic=5379.msg105544#msg105544 "Re: FPGA mining"]. Bitcointalk.org. Retrieved February 7, 2013.</ref> || || 0.13 || || 595<ref name="de2">[http://www.terasic.com.tw/cgi-bin/page/archive.pl?No=502 "Altera DE2-115 Development and Education Board"]. Terasic. Retrieved January 30, 2013.</ref>
|-
! X6500 FPGA Miner
| 400<ref name="x65" /> || 23.25 || 0.72 || 17.2<ref name="x65" /> || 550<ref name="x65">[http://store.fpgamining.com/ "FPGA Mining Store"]. FPGA Mining. Retrieved January 30, 2013.</ref>
|-
! ZTEX USB-FPGA Module 1.15b
| 90<ref name="miner" /> || || 0.27 || || 325<ref>http://shop.ztex.de/product_info.php?cPath=21&products_id=62</ref>
|-
! ZTEX USB-FPGA Module 1.15x
| 215<ref name="miner" /> || || 0.52 || || 406<ref>http://shop.ztex.de/product_info.php?cPath=21&products_id=66</ref>
|-
! ZTEX USB-FPGA Module 1.15y
| 860<ref name="miner">http://www.ztex.de/btcminer/</ref> || || 0.65 || || 1,304<ref name="1.15y">http://shop.ztex.de/product_info.php?cPath=21&products_id=74</ref>
|}
<references/>

* [https://www.weusecoins.com/en/mining-guide/ Getting Started With Bitcoin Mining]
* [https://www.bitcoinmining.com/ Bitcoin Mining]
* [https://www.bitcoinmining.com/bitcoin-mining-hardware/ Bitcoin mining hardware]

Non-specialized hardware comparison

2015-08-04T14:40:23Z

Sunnankar: /* See Also */

==Graphics cards==
Due to the rising hashrate of the bitcoin network caused by the introduction of ASICs to the market, GPU mining Bitcoins has become impracticable. The hashrate of most GPU units is below 1GH/s, and as of 2014, some single ASIC units are able to reach speeds of over 1,000GH/s while consuming far less power than used by a GPU. The information in this table is preserved for historical interest, but does not include many GPUs which were released after the advent of ASIC mining.

===AMD (ATI)===
Stream SDK 2.5 seems to have resolved many of the problems with earlier versions. Everyone's setups will be unique so this should only be a guide or starting point, not an absolute.

{| class="wikitable sortable"
|-
! Model !! Mhash/s !! Mhash/J !! Mhash/s/$<ref name='amazon_20110625'/> !! Watts !! Clock !! SP !! SDK !! Slot !! Miner !! Notes
|-
| 3410 || 0.89 || 0.074 || ? || 12(?) || 222 || 40 || 1.4 beta || PCI-E 1.1 x8 || A custom Brook+ miner || Using 16,384 length streams
|-
| 3XXX || || || || || || || || || || OpenCL Not Supported
|-
| 42XX || || || || || || || || || || OpenCL Not Supported (integrated/mobile GPU)
|-
| 4350 || 6.93 || 0.346 ||0.16 || 20 || 575 || 80 || - || PCI-E 2.0 x16 || poclbm || -w 32, don't use vectors
|-
| 4350 || 7.2 || || || || 600 || || 1.1 || PCI-E 2.0 x16 || cgminer/Linux || default settings
|-
| 4350 || 8.14 || -|| 0.19 || - || 730 || 80 || 2.4 || PCI-E 2.0 x16 || Diablo/Windows7 || -w 32. Model: Asus EAH4350 Silent. Memory at 400MHz. Runs at 60°C with ambient at 25°C.
|-
| 4350 || 10.7 || -|| - || - || 730 || - || 2.6 || PCI-E 2.0 x16 || CGMiner/Windows7 || -v -w 64 Voltage set at 0.900 core set at 800MHZ and memory set to 200MHZ
|-
| 4550 || 7.23 || 0.289 ||0.13 || 25 || 600 || 80 || - || PCI-E 2.0 x16 || poclbm || -w 32, don't use vectors
|-
| 4550 || 7.8 || || || || || || - || PCI-E 2.0 x16 || guiminer /phoenix || worksize=64 VECTORS
|-
| 4570M || 8.02 || 0.297 || ? || 27 || 680 || 80 || - || PCI-E 2.0 x16 || Diablo/Windows7 || -w 64, SDK 2.4, Cat 11.4. Model: Sony Vaio NW
|-
| 4570M || 9.6 || 0.300|| ? || 32 || 825(OC) || 80 || - || PCI-E 2.0 x16 || Diablo/Windows7 || -w 64, SDK 2.4, Cat 11.4. Model: Sony Vaio NW. OC core 680->825. U/C memory 800->500.
|-
| 4650 || 31.33 || 0.653|| 0.44 || 48 || 650 || 320 || - || PCI-E 2.0 x16 || poclbm || -w 32, don't use vectors
|-
| 4670 || 36.14 || 0.613|| 0.34 || 59 || 750 || 320 || - || PCI-E 2.0 x16 || poclbm || -w 32, don't use vectors
|-
| 4670 || 40.11 || 0.679|| 0.38 || 59 || 800 || 320 || - || AGP x8 || poclbm/Ubuntu 10.10 w/ H == 0 mod || -w 32 -f 0, don't use vectors [http://www.bitcoin.org/smf/index.php?topic=1334.msg85236#msg85236 source]
|-
| 4670 || 50 || - || 0.47 || 60 || 800 || 320 || - || PCI-E 2.0 x16 || guiminer || 2 miners set up i7 920 (130W), CPU: Ufasoft, GPU: OpenCL; the CPU is getting about 40 Mhash/s while the GPU goes from 10-20 Mhash/s
|-
| 4730 || 72.29 || 0.657|| ? || 110 || 750 || 640 || - || PCI-E 2.0 x16 || - ||
|-
| 4770 || 72.29 || 0.904|| 0.72 || 80 || 750 || 640 || - || PCI-E 2.0 x16 || - ||
|-
| 4830 || 55.42 || 0.583|| || 95 || 575 || 640 || - || PCI-E 2.0 x16 || - ||
|-
| 4830 || 61.7 || - || || - || 700 || - || 2.4 || PCI-E 2.0 x16 || poclbm-mod || Fedora 14
|-
| 4830 || 64.9 || - || - || - || 700 || - || 2.4 || PCI-E 2.0 x16 || poclbm-mod || Fedora 14
|-
| 4830 || 66.12 || 0.503|| || 105 || 700 || 1005 || - || PCI-E 2.0 x16 || - ||
|-
| 4850 || 75.30 || 0.685 || || 110 || 625 || 800 || - || PCI-E 2.0 x16 || - ||
|-
| 4850 || 84.3 || 0.766 || || 110 || 725 || 300 || - || PCI-E 2.0 x16 || - || -w64 fan at 70% temp 73C, stock voltage -gui miner
|-
| 4850 || 87.4 || 0.79 || - || 110 || 785 || 800 || - || PCI-E 2.0 x16 || guiminer || Phoenix; -k poclbm
|-
| 4850 || 90.1 || 0.819 || || 110 || 800 || 500 || - || PCI-E 2.0 x16 || guiminer || -f 30; Tried phoenix and phatk, got same max
|-
| 4850 || 101 || 0.918 || || 110 || 817 || 500 || 2.1 || PCI-E 2.0 x16 || guiminer || -f 0, core 817mhz(default 625)@1.123v , mem downclock to 500mhz (default 993) [http://www.smpake.com/?p=6 source]
|-
| 4850x2 || 150.60 || 0.602 || || 250 || 625 || 1600 || - || PCI-E 2.0 x16 || - ||
|-
| 4860 || 67.47 || 0.519|| || 130 || 700 || 640 || - || PCI-E 2.0 x16 || - ||
|-
|style="background:#F8F8FF;"| 4870 || 78 || 0.520|| || 150 || - || - || - || PCI-E 2.0 x16 || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]
|-
|style="background:#F8F8F8;"| 4870 || 88 || || || 140 || std || 800 || 12.3.6 || PCI-E 2.0 x16 || phoenix 1.50 / 64bit OS X pyopencl / poclbm || Standard Mac Pro 3,1 with Apple HD4870 upgrade. Flags: FASTLOOP WORKSIZE=64 AGGRESSION=5 (don't use vectors, and hash rate drops to 60-70 if browser windows are visible, speeds up to 88 if you hide them!
|-
|style="background:#F8F8FF;"| 4870 || 90.36 || 0.602|| || 150 || 750 || 800 || 2.1 || PCI-E 2.0 x16 || clmine ||
|-
|style="background:#F8F8FF;"| 4870 || 92.84 || 0.6189333(?)|| || 150(?) || 830(OC) || 800 || 2.4 || PCI-E 2.0 x16 || Phoenix 1.48 || -k poclbm AGGRESSION=5 (Windows 7 64-Bit, GPU OC 750->830MHz, VRAM UC 900->450MHz, BIOS modded)
|-
|style="background:#F8F8F8;"| 4870 || 96 || || || 140 || 750 || 800 || 2.4 || PCI-E 2.0 x16 || Smartcoin r657s / phoenix 1.50 / Linuxcoin 0.2b final || Powercolor @ GPU 830 MHz/ MEM 200 Mhz @ 80% FAN @ 69 temp @ Flags: -k phatk bfi_int=false FASTLOOP=false WORKSIZE=256 AGGRESSION=11
|-
|style="background:#F8F8F8;"| 4870 || 104 || || || 140 || 750 || 800 || 2.4 || PCI-E 2.0 x16 || Smartcoin r657s / DiabloMiner / Linuxcoin 0.2b final || Powercolor @ GPU 830 MHz/ MEM 200 Mhz @ 80% FAN @ 69 temp @ Flags: -v 1 -w 256
|-
|style="background:#F8F8FF;"| 4870 || 104.2 || ?|| || ? || 830(OC) || 800 || 2.1 || PCI-E 2.0 x16 || poclbm || Windows 7 64-Bit, GPU Core OC to 830 MHz, GPU Memory UC to 200 MHz By MSI AfterBurner. Card: Gainward Golden Sample. @70%Fan we have 55 GPU temp.
|-
|style="background:#F8F8FF;"| 4870 || 104.6 || 0.872|| || 120 || 830(OC) || 800 || 2.1 || PCI-E 2.0 x16 || poclbm || -w 256 -f 1, Windows 7 64-Bit, GPU Core OC to 830 MHz, GPU Memory UC to 190 MHz (saves 30 watts at outlet)
|-
|style="background:#F8F8F8;"| 4870 || 112 || || || 140 || 750 || 800 || 2.4 || PCI-E 2.0 x16 || BAMT 0.5c / cgminer || Powercolor @ GPU 875 MHz/ MEM 300 Mhz/ 1,25VDC @ 100% FAN @ 65 temp @ Flags: -v 1 -w 256
|-
|style="background:#F8F8FF;"| 4870x2 || 180.6|| 0.632|| || 286 || 800 || 1600 || - || PCI-E 2.0 x16 || - ||
|-
|style="background:#F8F8FF;"| 4870x2 || 180.72|| 0.632|| || 286 || 750 || 1600 || - || PCI-E 2.0 x16 || - ||
|-
| 4870x2 || 203 || || || || 850(OC) || 1600 || 2.6 || PCI-E 2.0 x16 || poclbm-mod ver. 20 april 2011|| Gainward / Win7 x64 / -w 256 -f 1 / 850MHz GPU - 300MHz Mem - 1,262V - 100% fun : 72C
|-
| 4890 || 97.1 || 0.511|| || 190 || 870(OC) || 1050 || 2.4 || PCI-E 2.0 x16 || GUIMiner v2011-01-21 Solo settings || Sapphire fab. No flags options helped. Close all browsers and do full restart of GUIMiner and then Bitcoin via GUIMiner server starter or the browsers GPU accl. will limit to 56~ ish Mhash/s - I can now start browser without slowdowns
|-
| 4890 || 102.41 || 0.539|| || 190 || 850 || 800 || - || PCI-E 2.0 x16 || - ||
|-
| 4890 || 108.3 || 0.57|| || 190 || 975 || 800 || - || PCI-E 2.0 x16 || - ||
|-
| 4890 || 121.5 || -|| || 190 || 1025 (OC) || 800 || 2.4 || PCI-E 2.0 x16 || poclbm || no flags, Vcore 1.4
|-
|style="background:#FFF8EF;"| 5450 || 11.99|| 0.631|| || 19 || 650 || 80 || - || PCI-E 2.1 x16 || - ||
|-
|style="background:#FFF8EF;"| 5450 || 13.74|| || - || - || 700 || - || - || PCI-E 2.1 x16 || poclbm/Linuxcoin v0.2 || -v -w128 tried several options, seems to work best.
|-
|style="background:#FFF8EF;"| 5450 || 14.12|| || - || - || 700 || - || - || PCI-E 2.1 x16 || Phoenix/Linuxcoin v0.2 || Flags: "DEVICE=0 VECTORS AGGRESSION=4 -v FASTLOOP BFI_INT WORKSIZE=64" Kernel: "phatk"
|-
|style="background:#FFF8EF;"| 5450 || 15.36|| || - || - || 700 || - || - || PCI-E 2.1 x16 || Phoenix || Flags: "DEVICE=0 VECTORS AGRESSION=8 FASTLOOP BFI_ING WORKSIZE=128" Kernel: "phatk" - MagicSata
|-
|style="background:#FFF8EF;"| 5450 || 18.10|| || - || - || 774 || - || - || PCI-E 2.1 x16 || poclbm || -v -w 128 -f 1 774.66MHz/300.37MHz
|-
|style="background:#FFF8EF;"| 5470 || 17.10|| || - || - || - || - || - || - || poclbm || -v -w 128 MobileGPU
|-
| 5550 || 40.59 || 1.041|| || 39 || 550 || 320 || - || PCI-E 2.1 x16 || - ||
|-
| 5550 || 62.10 || - || - || - || 700 || - || - || PCI-E 2.1 x16 || Phoenix || 700MHz core 800MHz ram, phatk mod, Flags: "-k phatk worksize=128 vectors aggression=4 bfi_int"
|-
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538|| || 39 || 650 || 400 || - || PCI-E 2.1 x16 || - ||
|-
|style="background:#FFFFEF;"| 5570 || 62 || 1.59|| || 39 || 650 || 400 || 2.4 || PCI-E 2.1 x16 || Phoenix 1.48 OpenCL/Linux x86_64 || -k phatk DEVICE=0 VECTORS AGGRESSION=4 -v FASTLOOP BFI_INT WORKSIZE=64
|-
|style="background:#FFFFEF;"| 5570 || 64 || 1.641|| || 39 || 650 || - || - || PCI-E 2.1 x16 || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]
|-
|style="background:#FFFFEF;"| 5570 || 73 || 1.872|| || 39 || 700 || 400 || 2.4 || PCI-E 2.1 x16 || Phoenix 1.48 OpenCL/Linux x86_64 || -k phatk DEVICE=0 VECTORS AGGRESSION=4 -v FASTLOOP BFI_INT WORKSIZE=64
|-
|style="background:#FFFFEF;"| 5570 || 86.3 || 2.397|| || 36 || 775 || 300 || 2.4 || PCI-E 2.1 x16 || Phoenix 1.75 OpenCL/Windows 7 x64 (no Aero) ||-k phatk VECTORS BFI_INT FASTLOOP=false AGGRESSION=11 -v WORKSIZE=256 Fan 100% 86C Undervolted @ 0.96v using Sapphire Trixx
|-
|style="background:#FFFFEF;"| 5570 || 94 || stock || || || 880 || 800 || 2.4 || PCI-E 2.1 x16 || GUI Miner 02-12/Windows 7 x86 || -v -w128 75C
|-
|style="background:#FFFFEF;"| 5570 || 102 || 1.46(+)|| || 75(-) || 950 || 400 || 2.4 || PCI-E 2.1 x16 || Phoenix 1.48 OpenCL/Windows 7 x86 (no Aero) || -k phatk DEVICE=0 VECTORS AGGRESSION=7 -v FASTLOOP BFI_INT WORKSIZE=256 (Reference Sapphire card, 2 additional 120mm coolers, temperature is 79-82C)
|-
| 5650 || 48 || 1.37|| || 35(?) || - || - || - || PCI-E 2.1 x16 || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source] -- not TDP but load
|-
| 5650 || 61.2 || || || 35 || || || 2.4 || PCI-E 2.1 x16 || Phoenix 1.50 OpenCL/Windows 7 x64 || -k phatk DEVICE=0 VECTORS BFI_INT WORKSIZE=128 AGGRESSION=9
|-
|style="background:#EEFFEE;"| 5670 || 71.49 || 1.117|| || 64 || 775 || 400 || - || PCI-E 2.1 x16 || - ||
|-
|style="background:#EEFFEE;"| 5670 || 72 || 1.64|| || 44 || 850 || - || - || PCI-E 2.0 x16 || poclbm-mod (Win7-64) || Sapphire 100287VGAL card is low power
|-
|style="background:#EEFFEE;"| 5670 || 85|| || - || - || 900 || 400 || - || PCI-E 2.1 x16 || poclbm || -v -f 0 -w 128
|-
|style="background:#EEFFEE;"| 5670 || 91|| || - || - || 890 || 400 || - || PCI-E 2.1 x16 || guiminer 2011-06-09 poclbm catalyst 11.2 win7 x86 || -v -f 0 -w 128
|-
|style="background:#EEFFEE;"| 5670 || 100|| || - || - || 890 || 400 || - || PCI-E 2.1 x16 || cgminer 1.5.6 || GPU/Mem 890/800 temp 72C
|-
|style="background:#EEFFEE;"| 5670 || 103 || -|| || - || 900/275 || 400 || 2.4 || PCI-E 2.1 x1 || phoenix-1.50 / phatk-mod / Ubuntu 11.04 || VECTORS BFI_INT FASTLOOP=false AGGRESSION=11 WORKSIZE=256 / small fan, under 50 deg C, no voltage tweaks... catfish
|-
|style="background:#EEFFEE;"| 5670 || 127.8|| || - || - || 850 || - || - || PCI-E 2.1 x16 || Windows 7 (64bit) Phoenix 2.0 || Aggression=11 Worksize=128 Fastloop=False Opencl
|-
| 5750 || 105 || - || - || - || - || - || - || - || poclbm || Apple iMac 27inch (Mid 2010), Mac OSX 10.7 Lion
|-
| 5750 || 116.24 || 1.352|| || 86 || 700 || 720 || - || PCI-E 2.1 x16 || - ||
|-
| 5750 || 137 || ||- || - || 710 || 720 || - || PCI-E 1.1 x16 || poclbm || -v -f 0 -w 128 using stock memory and GPU clocks
|-
| 5750 || 146.4 || || - || - || 775 || 720 || - || PCI-E 2.0 x16 || GUIMiner v2011-05-21 || -v -w128, AMD Catalyst overclock (775MHz GPU / 1225 MHz Memory)
|-
| 5750 || 154.56 || 1.45|| || 106 || 830 || 720 || - || PCI-E 2.1 x16 || - || -v -w128 -f20 underclocked memory clocks from 1150MHz to 300MHz
|-
| 5750 || 170 || - || || - || 870 || 720 || - || PCI-E 1.1 x16 || poclbm || -v -f 0 -w 128 patched BIOS to underclock memory to 300MHz
|-
| 5750 || 173 || - || ||- || 875 || 720 || - || PCI-E 1.1 x16 || phoenix || 875/300 w/MSI Afterburner, BFI_INT VECTORS AGGRESSION=12 FASTLOOP=FALSE -k phatk
|-
| 5750 || 177 || - || ||- || 910/575 || 720 || 2.6 || PCI-E 2.0 x8 || phoenix 1.5.6 || PowerColor GoGreen+fan, MSI Afterburner 2.2Beta, -k phatk VECTORS AGGRESSION=12 FASTLOOP=FALSE WORKSIZE=64
|-
| 5750 || 190 || - || ||- || 930/290 || - || atistream sdk || PCI-E 1.1 x16 || poclbm || 930gpu / 290mem (O.S. Ubuntu 10.10 x64, overclock gpu & underclock mem) with poclbm options -v -f 0 -w 256
|-
| 5750 Vapor-X || 195 || - || - || 125 || 975/300 || - || 2.4 || PCI-E 1.1 x16 || cgminer 2.7.5 || (O.S. Ubuntu 12.01 AMD64 dedicated) cgminer options -Q 0 -I 9 -g 2 -w 256 --auto-fan --temp-target 65 --gpu-vddc 1.075 (Fan speed 60~65%)
|-
| 5750x2 CF || 356 || - || ||- || 870 || 720x2 || 2.4 || PCI-E 2.0 x16 || [http://forum.bitcoin.org/index.php?topic=28402.0 cgminer v1.5.1] (Win7 64bit) || 870MHz GPU / -I 8 / 2x [http://www.gigabyte.com/products/product-page.aspx?pid=3402#sp GIGABYTE GV-R575SL-1GI] cards + [http://www.gigabyte.com/products/product-page.aspx?pid=3258#sp GIGABYTE GA-790FXTA-UD5] MB + 1x [http://www.noctua.at/main.php?show=productview&products_id=9&lng=en 80mm], 1x [http://www.noctua.at/main.php?show=productview&products_id=16&lng=en 90mm] Noctua coolers
|-
|style="background:#FFFFEF;"| 5770 || 156.83 || 1.452|| || 108 || 850 || 800 || 2.1 || PCI-E 2.1 x16 || clmine ||
|-
|style="background:#FFFFEF;"| 5770 || 171.12 || - || - || - || - || stock || - || PCI-E 2.1 x16 || phoenix 1.7.3/debian gnu/linux 6 squeeze || -k phatk2 DEVICE=0 VECTORS BFI_INT FASTLOOP=false AGGRESSION=12 WORKSIZE=256
|-
|style="background:#FFFFEF;"| 5770 || 180 || 1.406(*)|| || 128(*) || 950(OC) || 800 || 2.4RC1 || PCI-E 2.1 x16 || poclbm || -v -w 128 -f 30 (*: Overclocked wattage calculated [http://bakkap.free.fr/Misc/wCalc.html here])
|-
|style="background:#FFFFEF;"| 5770 Hawk || 182 || ||- || - || 875 || 800 || 2.4 || PCI-E 2.0 x16 || poclbm/GUIMiner/Win7-64 || -v -w 128 (875MHz is stock for 5770 Hawk)
|-
|style="background:#FFFFEF;"| 5770 || 185 || - || ||- || 850 || 1200 || 2.4 || PCI-E 2.1 x16 || phoenix 1.48 / phatk || -k phatk VECTORS BFI_INT WORKSIZE=128 FASTLOOP AGGRESSION=7
|-
|style="background:#FFFFEF;"| 5770 || 205.58 || - || ||- || 935 || 300 || 2.1 || PCI-E 2.1 x16 || poclbm 2011-04-28 || -v -w 256
|-
|style="background:#FFFFEF;"| 5770 || 214.5 || 1.95(-)|| || 108(+) || 950 || 300 || 2.4 || PCI-E 2.1 x16 || phoenix 1.50/GUIMiner/Win7-64 || mem underclocked 300 mhz, 1.1vcore, 950mhz core, @69°C/57%FAN VECTORS BFI_INT AGGRESSION=12 -k phatk WORKSIZE=256
|-
|style="background:#FFFFEF;"| 5770 || 214.7 || 1.95(-)|| || 108(+) || 950 || 800 || 2.4 || PCI-E 2.1 x16 || phoenix 1.48 / win7x86 || mem underclocked 309 mhz, -k phatk DEVICE=0 VECTORS BFI_INT FASTLOOP=false AGGRESSION=12
|-
|style="background:#FFFFEF;"| 5770 || 216.5 || -|| || - || 955 || || 2.1 || PCI-E 2.0 x16 || Phoenix 1.5 /phatk || [http://forum.bitcoin.org/index.php?topic=23067.0 Modified phatk kernel] and stock voltage for Sapphire (1.125V) VECTORS BFI_INT FASTLOOP=false AGGRESSION=12 -k phatk WORKSIZE=256
|-
|style="background:#FFFFEF;"| 5770 || 218.35 || -|| || - || 1000 || 1401 || 2.1 || PCI-E 2.0 x16 || DiabloMiner || -w 128 -v 2 (Overclocked to 1Ghz core with 1.2 voltage and Scythe Setsugen 2 cooling system)
|-
|style="background:#FFFFEF;"| 5770 || 223 || 2.23(-)|| || 100(+) || 1050 || 300 || 2.4 || PCI-E 2.1 x16 || guiminer || -v -w256 [http://www.smpake.com/?p=59 source]
|-
|style="background:#FFFFEF;"| 5770 || 227 || -|| || - || 1030 || 800 || 2.1 || PCI-E 2.0 x16 || DiabloMiner || -w 256 -v 2 (Overclocked to 1030 core/300 mem with 1.2 voltage and Scythe Setsugen 2 cooling system)
|-
|style="background:#FFFFEF;"| 5770 || 233 || 2.23(-)|| || 100(+) || 1050 || 300 || 2.4 || PCI-E 2.1 x16 || phoenix 1.48 || VECTORS BFI_INT FASTLOOP=false AGGRESSION=12 -k phatk WORKSIZE=256 [http://www.smpake.com/?p=59 source]
|-
|style="background:#FFFFEF;"| 5770 || 236 || -|| || - || 1033/275 || 800 || 2.4 || PCI-E 2.1 x16 || phoenix-1.50 / phatk-mod / Ubuntu 10.04 || VECTORS BFI_INT FASTLOOP=false AGGRESSION=11 WORKSIZE=256 / big fans, under 75 deg C, no voltage tweaks... catfish
|-
|style="background:#FFFFEF;"| 5770 || 240.61 || 2.3632(-)|| || 100(+) || 1080 || 300 || 2.4 || PCI-E 2.1 x1 || phoenix 1.48 || VECTORS BFI_INT FASTLOOP=false AGGRESSION=12 -k phatk WORKSIZE=256 (OC'd and OV'd 1080/300 1.25v)
|-
|style="background:#FFFFEF;"| 5770 || 241 || - || - || 100(+) || 1045 || 250 || 2.1 || PCI-E 2.1 x16 || phoenix 1.50 || VECTORS BFI_INT AGGRESSION=13 -k phatk WORKSIZE=256 (OC 1020/300) XFX@1.1 volts. +Kernel function improve 5%
|-
|style="background:#FFFFEF;"| 5770 || 244 || -|| || - || 1050 || 300 || 2.1 || PCI-E 2.0 x16 || Phoenix 1.75 /phatk2 || [http://forum.bitcoin.org/index.php?topic=23067.0 Modified phatk kernel] and stock voltage for Sapphire (1.125V) VECTORS BFI_INT FASTLOOP=false AGGRESSION=9, Temp 75C, FAN 100% (manual)
|-
|style="background:#FFFFEF;"| 5770x2 || 425 || - || - || 225(+) || 960 || 800x2 || 2.1 || PCI-E 2.1 x16 || poclbm (guiminer) Win7x64 || -v -w128 (OC 960/1200)
|-
|style="background:#FFFDDD;"| 5830M || 120 || -|| || - || 570|| 120 || 2.4 || PCI-E 2.1 x16 || Phoenix 1.50 OpenCL/Win7 x64|| -k phatk DEVICE=0 VECTORS BFI_INT AGGRESSION=13 FASTLOOP=false
|-
|style="background:#FFFDDD;"| 5830 || 244 || 1.36|| || 179 || 800 || 1000 || 2.4 || PCI-E 2.1 x16 || Phoenix 1.48 OpenCL/Linux x86_64 || -k phatk DEVICE=1 VECTORS AGGRESSION=6 -v FASTLOOP WORKSIZE=128 BFI_INT
|-
|style="background:#FFFDDD;"| 5830 || 245 || 1.28|| || 192 || 880 || 900 || 2.4 || PCI-E 2.1 x16 || poclbm (guiminer) || -v -w 256
|-
|style="background:#FFFDDD;"| 5830 || 248 || 1.29|| || 192 || 880 || 500 || 2.4 || PCI-E 2.1 x16 || phoenix 1.46 || -k poclbm VECTORS BFI_INT AGGRESSION=11
|-
|style="background:#FFFDDD;"| 5830 || 256 || -|| || - || 900 || 300 || 2.4 || PCI-E 2.1 x16 || phoenix 1.48 || -k poclbm VECTORS BFI_INT AGGRESSION=7
|-
|style="background:#FFFDDD;"| 5830 || 267 || -|| || - || 875 || 1000 || 2.4 || PCI-E 2.1 x1 || Phoenix 1.48 OpenCL/Linux x86_64 || -k phatk DEVICE=1 VECTORS AGGRESSION=6 -v FASTLOOP WORKSIZE=128 BFI_INT
|-
|style="background:#FFFDDD;"| 5830 || 272 || 1.52|| || 179 || 875 || - || 2.4 || PCI-E 2.1 x16 || phoenix 1.48 / phatk / LinuxCoin || 275Mhz Memory clock, 1.125 V (from 1.163), VECTORS AGGRESSION=12 BFI_INT
|-
|style="background:#FFFDDD;"| 5830 || 275 || 1.5714|| || 175 || 900 || 500 || 2.1 || PCI-E 2.1 x16 || poclbm (guiminer) Win7x64 || -v -w64 -f10, XFX stock w/ v2.4 SDK = 230Mh/s, v2.1 SDK = +10Mh/s, overclocking core clock by 100 = +30Mh/s, underclocking memory to 500 (ran cooler), and changing workload to -w64 = +5Mh/s.
|-
|style="background:#FFFDDD;"| 5830 || 285 || - ||1.58 || - || 960 || - || 2.4 || PCI-E 2.1 x16 || phoenix 1.47 / poclbm / Win7 64 || VECTORS BFI_INT FASTLOOP=false AGGRESSION=12
|-
|style="background:#FFFDDD;"| 5830 || 290 || -|| || - || 930 || - || 2.2 || PCI-E x16/x4/x1 || GUIMiner / phoenix 1.5 / POCLBM / Win 7 64 || POCLBM VECTORS BFI_INT WORKSIZE=256 AGGRESSION=12 FASTLOOPS=false / Memory 300Mhz, VCore standard
|-
|style="background:#FFFDDD;"| 5830 || 290 || -|| || - || 996 || - || 2.4 || PCI-E 2.1 x16 || phoenix 1.4 / poclbm / Win7 64 || VECTORS AGGRESSION=12 BFI_INT
|-
|style="background:#FFFDDD;"| 5830 || 295 || -|| || - || 980 || 1120 || 2.1 || PCI-E 2.1 x16 || GUIMiner / poclbm / Win XP 32 || Extra flags -v -w 128
|-
|style="background:#FFFDDD;"| 5830 || 297 || -|| || - || 970 || 1120 || 2.4 || PCI-E 2.0 x16 || guiminer / phoenix 1.48 / phatk / Win7 64 || 300Mhz Memory clock, 44% fan-speed, -k phatk VECTORS BFI_INT AGGRESSION=8 FASTLOOP=false WORKSIZE=256
|-
|style="background:#FFFDDD;"| 5830 || 300 || -|| || - || 960|| 300 || 2.4 || PCI-E 2.1 x16 || GUIMiner / poclbm / Win 7 64 || Extra flags -v -w 256 (Sapphire Extreme 71 degrees @ 52% fan)
|-
|style="background:#FFFDDD;"| 5830 || 300 || -|| || - || 970 || - || 2.4 || PCI-E 2.0 x16 || phoenix 1.47 / pheonix 1.48 / Win7 64 || (sapphire xtreme) VECTORS BFI_INT FASTLOOP=false AGGRESSION=12
|-
|style="background:#FFFDDD;"| 5830 || 300 || -|| || - || 970 || 1120 || 2.1 || PCI-E x16 || phoenix 1.48 / phatk / Win7 64 || 300Mhz memory clock BFI_INT AGGRESSION=12 FASTLOOP=false WORKSIZE=256
|-
|style="background:#FFFDDD;"| 5830 || 305 || -|| || - || 984 || - || 2.4 || PCI-E 2.1 x16 || phoenix 1.4 / phatk / Win7 32 || 400Mhz Memory clock, VECTORS AGGRESSION=12 BFI_INT FASTLOOP=false
|-
|style="background:#FFFDDD;"| 5830 || 307 || -|| || - || 996 || - || 2.4 || PCI-E 2.1 x16 || phoenix 1.48 / phatk / Win7 64 || VECTORS AGGRESSION=12 BFI_INT
|-
|style="background:#FFFDDD;"| 5830 || 307 || 2.25 || 2.55 || 125 || 965 || - || - || PCI-E 2.1 x16 || cgminer 2.0.5 / Win7 64 || Mem @ 300/Stock voltage/Entire system 200W
|-
|style="background:#FFFDDD;"| 5830 || 308 || -|| || - || 990 || 300 || 2.4 || PCI-E 2.1 x16 || phoenix 1.50 / poclbm / Xubuntu 11.04 x64 || VECTORS AGGRESSION=11 BFI_INT FASTLOOP=false WORKSIZE=256
|-
|style="background:#FFFDDD;"| 5830 || 308 || -|| || - || 990 || 375 || 2.1 || PCI-E 2.1 x16 || phoenix 1.48 / phatk / Win7 32 || @ stock voltage VECTORS AGGRESSION=11 -v FASTLOOP=false BFI_INT
|-
|style="background:#FFFDDD;"| 5830 black || 310 || ||- || - || 990 || 300 || 2.4 || PCI-E 2.1 x8 || LinuxCoin 0.2b, phoenix/phatk || (XFX Brand) -k phatk VECTORS BFI_INT WORKSIZE=256 AGGRESSION=11 FASTLOOPS=false
|-
|style="background:#FFFDDD;"| 5830 || 311 || -|| || - || 1000 || 300 || 2.4 || PCI-E 2.1 x16 || phoenix 1.50 / phatk / Linux || VECTORS BFI_INT AGGRESSION=13 FASTLOOP=false WORKSIZE=256
|-
|style="background:#FFFDDD;"| 5830 || 315 || -|| || - || 970 || - || 2.4 || PCI-E 2.1 x16 || phoenix 1.6.1 / phatk2 / CrunchBang Linux || memory @ 300mhz VECTORS BFI_INT AGGRESSION=9 WORKSIZE=256
|-
|style="background:#FFFDDD;"| 5830 || 316 || ||- || - || 1015 || 375 || 2.1 || PCI-E 2.1 x16 || phoenix 1.48 / phatk / Win7 32 || @ stock voltage VECTORS AGGRESSION=12 -v FASTLOOP=false BFI_INT
|-
|style="background:#FFFDDD;"| 5830 || 319 || -|| 1.77 || - || 1030 || - || 2.4 || PCI-E 2.1 x16 || phoenix 1.48 / phatk / Xp 64 || 1.2v 355Mhz Memory, VECTORS AGGRESSION=12 BFI_INT
|-
|style="background:#FFFDDD;"| 5830 || 321 || -|| || - || 1000 || 1120 || 2.4 || PCI-E 2.0 x16 || phoenix 1.50 / phatk-mod / Linux || 1000Mhz GPU, 350Mhz RAM, 1.15V, 90% fan, ~60c Temp, VECTORS BFI_INT FASTLOOP=false AGGRESSION=13 WORKSIZE=128; phatk kernel found [http://forum.bitcoin.org/index.php?topic=25135.0 here]
|-
|style="background:#FFFDDD;"| 5830 || 323 || || || || 900 (OC) || || 2.4 || PCI-E 2.1 x16 || phoenix 1.5 Win7x64 || (500Mhz RAM), ~61c Temp, 57% fan, BFI_INT FASTLOOP=false VECTORS AGGRESSION=12 -v WORKSIZE=64
|-
|style="background:#FFFDDD;"| 5830 (127$) || 325 || 1.98 || 2.57Mh/$ || 165W || 1040MHz || 200MHz || 2.6 || PCI-E 2.0 x8 || Guiminer/phatk-[http://forum.bitcoin.org/index.php?topic=25135.0 mod] w7 64bit || -k phatk AGGRESSION=12 VECTORS2 WORKSIZE=128 stock volt, watercooled 53C
|-
|style="background:#FFFDDD;"| 5830 || 328 || - || - || - || 1040 || - || 2.4 || PCI-E 2.1 x16 || LinuxCoin 0.2.1b / phoenix / phatk || 1.195 V, RAM @ 325 Mhz, fan @90%, no case, extra 10K RPM fan (62 deg.C in full-load); options: -k phatk DEVICE=0 VECTORS BFI_INT FASTLOOP=false AGGRESSION=11 WORKSIZE=256; brand: Sapphire Xtreme; bord is stable up to 1060 Mhz ~ 335 MHash, but produces some visual artefacts;
|-
|style="background:#FFFDDD;"| 5830 || 331 || - || 4.14 || - || 1010 || 1120 || 2.4 || PCI-E 1.0 x16 || WinXP 32 / Phoenix 1.7.5 / phatk2 || Stock Voltage, RAM 300, 64C, Fan 67%, -k phatk2 VECTORS BFI_INT AGGRESSION=11 WORKSIZE=256 FASTLOOP=false (+6Mh w/ Phoenix 1.7.5 over 1.6.2)
|-
|style="background:#FFFDDD;"| 5830 || 333 || - || - || - || 1040 || - || 2.4 || PCI-E 2.1 x16 || LinuxCoin 0.2.1b / phoenix-1.50 / phatk-[http://forum.bitcoin.org/index.php?topic=25135.0 mod] || + ~5 Mhash increase using the modified phatk from the user above. I am the same guy with 330 @ 1040 MHz Sapphire Xtreme, all other settings the same, board stable, no increase in rejected
|-
|style="background:#FFFDDD;"| 5830 || 334 || -|| || - || 1040 || - || 2.5 || PCI-E 2.0 x16 || phoenix 1.75 / phatk 2.2 / Win7 64 || Stock voltage, 208Mhz Memory, VECTORS AGGRESSION=12 WORKSIZE=128 BFI_INT
|-
|style="background:#FFFDDD;"| 5830 || 334 || -|| || - || 1030 || - || 2.4 || PCI-E 2.1 x16 || phoenix 1.50 / phatk 2.0 / Win7 64 || Stock voltage, 385Mhz Memory, VECTORS AGGRESSION=12 WORKSIZE=256 BFI_INT -- (upped from 330 achieved with diapolo mod [http://forum.bitcoin.org/index.php?topic=25135.0 here]), now using phatk 2.0 found [http://forum.bitcoin.org/?topic=7964.0 here]
|-
|style="background:#FFFDDD;"| 5830 || 342 || - || - || - || 1045 || - || 2.4 || PCI-E 2.0 x8 || phoenix 1.48 / phatk 2.2 / WinSvr 2008 R2 64 || Stock voltage, 385Mhz Memory, VECTORS VECTORS4 FASTLOOP=false AGGRESSION=14 BFI_INT -k phatk-2.2
|-
|style="background:#FFFDDD;"| 5830x2 CF || 480 || -|| || - || 800 || - || 2.4 || PCI-E 2.1 x16 || Guiminer/ - / Win7 64bit |Guiminer || -v -f70 -w128
|-
|style="background:#FFFDDD;"| 5830x2 || 570 || -|| || - || 950 || - || 2.4 || PCI-E 2.1 x8 || Guiminer/ - / Win7 64bit poclbm || poclbm -v -w256 -f10 MEMORYCLOCK 300MHZ GPUCLOCK 950MHZ FAN 52% 72°C
|-
|style="background:#FFFDDD;"| 5830x2 || 608 || -|| || - || 990 || - || - || 2x PCI-E 2.0 x16 || phoenix 2.0/ phatk2 / Win7 32bit || Stock voltage, 300Mhz Memory, VECTORS GOFFSET AGGRESSION=12 WORKSIZE=256 BFI_INT FAN 51% 69°C (Open ATX case)
|-
|style="background:#FFFDDD;"| 5830x6 || 1967 || 1.62 || 1.97 || - || 1020/340 || 1120x6 || 2.4 || PCI-E 2.1 x1 || Phoenix 1.7.5/phatk2/BAMT Linux || 100% fan @65C / 1.162V / CCC 11.6 / BFI_INT VECTORS FASTLOOP=false AGGRESSION=11 WORKSIZE=256
|-
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595|| 1.49 || 151 || 725 || 1440 || - || PCI-E 2.1 x16 || - ||
|-
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657|| || 151 || 725 || 1440 || - || PCI-E 2.1 x16 || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]
|-
|style="background:#EFEFFF;"| 5850 || 252 || 1.575|| || 160 || 765 || 1440 || 2.3 || PCI-E 2.1 x16 || poclbm 2011-01-25 ||
|-
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.593|| || 160 || 765 || 1440 || 2.2 || PCI-E 2.1 x16 || poclbm 2011-01-25 ||
|-
|style="background:#EFEFFF;"| 5850 || 264 || 1.748|| || 151 || 725 || 1440 || 2.4 || PCI-E 1.0 x8 || guiminer-20110501 || -v -w128
|-
|style="background:#EFEFFF;"| 5850 || 280 || 1.75|| || 160 || 765 || 1440 || 2.2 || PCI-E 2.1 x16 || Phoenix 1.3 || with BFI_INT
|-
|style="background:#EFEFFF;"| 5850 || 280 || - || ||- || 725 || 1440 || 2.1 || PCI-E 2.1 x16 || Phoenix 1.50 / Fedora 14 || -v -k poclbm VECTORS AGGRESSION=8 WORKSIZE=128 BFI_INT FASTLOOP=true
|-
|style="background:#EFEFFF;"| 5850 || 282.75 ||style="background:#EFEFFF;"| 3.06|| - || 92.25|| 666 (UC) || 1440|| 2.1 || PCI-E 2.1 x16 || Phoenix/WinXP || undervolted to 0.95V; phatk2 VECTORS BFI_INT AGGRESSION=11 WORKSIZE=256; driver 10.12; [http://bitcointalk.org/index.php?topic=9982.0 clocktweak] for setting values; [https://bitcointalk.org/index.php?topic=40056 thread]
|-
|style="background:#EFEFFF;"| 5850 || 292 || 1.825|| || 160 || 765 || 1440 || 2.1 || PCI-E 2.1 x16 || poclbm 2011-04-28 -v -f 1 ||
|-
|style="background:#EFEFFF;"| 5850 || 298 || 1.8620|| || 160 || 765 || 1440 || 2.1 || PCI-E 2.1 x16 || poclbm 2011-04-28 -v -f 1 -w 64 ||
|-
|style="background:#EFEFFF;"| 5850 || 300 || 1.5460|| || 194 || 925(OC) || 1440 || - || PCI-E 2.1 x16 || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]
|-
|style="background:#EFEFFF;"| 5850 || 304 || - || || - || 725 (stock) || 1440 || 2.1 || PCI-E 2.1 x16 || cgminer.exe -v 2 -I 8 -w 256 --gpu-memclock 275 ||
|-
|style="background:#EFEFFF;"| 5850 || 314 || 1.8362|| || 171 || 820(OC) || 1440 || 2.4 || PCI-E 1.0 x8 || poclbm || -v -w128
|-
|style="background:#EFEFFF;"| 5850 || 328 || - || || - || 875 @ Stock voltage || 1440 || 2.4 || PCI-E 2.1 x16 || phoenix || 70C @42% fan, mem @ 500mhz; -v -k phatk VECTORS BFI_INT AGGRESSION=8 FASTLOOP=false WORKSIZE=128
|-
|style="background:#EFEFFF;"| 5850 || 330 || - || ||- || 850 @ Stock voltage || 1440 || 2.1 || PCI-E 2.0 x16 || phoenix || EAH5850, miner arguments: -k poclbm DEVICE=1 VECTORS AGGRESSION=8 WORKSIZE=128 BFI_INT FASTLOOP=false
|-
|style="background:#EFEFFF;"| 5850 || 331 || - || ||- || 725 (Stock) || || 2.4 || PCI-E 2.0 x16 || Diablo Win7 64bits|| Sapphire 5850 Xtreme, Arguments: -v 2 -w 192 (by Swapper 2011-07-05)
|-
|style="background:#EFEFFF;"| 5850 || 335 || 1.8611|| || 180 || 890(OC) || 1440 || 2.4 || PCI-E 2.0 x8 || poclbm || -v -w128, Memory downclocked to 300Mhz
|-
|style="background:#EFEFFF;"| 5850 || 344 || 1.8594|| || 185 || 890(OC) || 1440 || - || PCI-E 2.0 x16 || phoenix ||
|-
|style="background:#EFEFFF;"| 5850 || 347 || -|| || - || 876 || 1440 || 2.4 || PCI-E 2.0 x16 || guiminer / phoenix 1.48 / phatk / Win7 64 || 300Mhz Memory clock, 50% fan-speed, -k phatk VECTORS BFI_INT AGGRESSION=11 FASTLOOP=false WORKSIZE=256
|-
|style="background:#EFEFFF;"| 5850 || 354 || -|| || - || 900(OC) || 1440 || 2.1 || PCI-E 2.0 x16 || diablo -v 2 -w 128 || Ubuntu 11.04 64-bit [http://forum.bitcoin.org/index.php?topic=9239.0 Headless], catalyst 11.5, memory downclocked to 300mhz, stock voltage. flashed with atiflash [http://www.youtube.com/watch?v=U9AxNmOy6_0 video]
|-
|style="background:#EFEFFF;"| 5850 || 355 || -|| || - || 900(OC) || 1440 || 2.1 || PCI-E 2.0 x16 || phoenix 1.48 / phatk || Ubuntu 11.04 64-bit, Memory downclocked to 200MHz, VECTORS BFI_INT FASTLOOP=false AGGRESSION=11 WORKSIZE=128
|-
|style="background:#EFEFFF;"| 5850 || 355 || -|| || - || 900 || 1440 || 2.1 || PCI-E 2.0 x16 || phoenix 1.48 / phatk / Ubuntu 11.04 x64 || 300Mhz Memory clock, 60% fan-speed, -k phatk VECTORS BFI_INT AGGRESSION=11 FASTLOOP=false WORKSIZE=256
|-
|style="background:#EFEFFF;"| 5850 || 356 || -|| || - || 870 (OC)|| 1440 || 2.5 || PCI-E 2.0 x16 || cgminer 2.1.2 / Win 7 x64 || 302Mhz Memory clock, 85% fan-speed, Stock Voltage, -I 6 -v 2 -w 256 (2012-02 by Swapper)
|-
|style="background:#EFEFFF;"| 5850 || 359 || -|| || - || 900 || 1440 || 2.4 || PCI-E 2.0 x16 || phoenix 1.50 / phatk / Ubuntu 11.04 x64 || 300Mhz Memory clock, 66% fan-speed, -k phatk VECTORS BFI_INT AGGRESSION=13 FASTLOOP=false WORKSIZE=256
|-
|style="background:#EFEFFF;"| 5850 || 365 || -|| || - || 920 || 1440 || 2.1 || PCI-E x16 || phoenix 1.48 / phatk / Win7 64 || 300Mhz memory clock VECTORS BFI_INT AGGRESSION=13 FASTLOOP=false WORKSIZE=256
|-
|style="background:#EFEFFF;"| 5850 || 367.5 || -|| || - || 900(OC) || 1440 || 2.1 || PCI-E 1.0 x16 || diablo with bitless's hack, -v 2 -w 128 || RHEL 5U5 x86_64, catalyst 11.5, Sapphire HD 5850 Xtreme, Memory downclocked to 300MHz, core voltage 1.145V, BIOS modded with RBE
|-
|style="background:#EFEFFF;"| 5850 || 369.4 || -|| || - || 930 || 1440 || 2.4 || PCI-E 1.0 x16 || guiminer / phoenix / phatk / Win7 32 || Catalyst 11.5, XFX HD5850, Memory downclocked to 322MHz, -k phatk VECTORS BFI_INT AGGRESSION=13 WORKSIZE=256
|-
|style="background:#EFEFFF;"| 5850 || 372 || 1.68 || - || 220 @ Wall || 900 || 300 || 2.5 || PCI-E 1.1 x8 || cgminer 2.3.1 from source / Ubuntu 11.11 x86_64 || -I 8 -v 2 -w 256 --- hex-core opteron cpu w/ 12GB RAM and cgminer CPU bug in linux makes power usage a little high ~210w in windows 7 x86_64
|-
|style="background:#EFEFFF;"| 5850 || 375 || -|| || - || 940 || 1440 || 2.4 || PCI-E 2.0 x16 || phoenix 1.50 / phatk / Ubuntu 10.04 || 300Mhz memory clock VECTORS AGGRESSION=13 WORKSIZE=256 BFI_INT FASTLOOP=false
|-
|style="background:#EFEFFF;"| 5850 || 381 || -|| || - || 940 || 1440 || 2.5 || PCI-E 1.0 x16 || phoenix / phatk / Win7 x64 / Catalyst 11.6 || MSI Afterburner 500MHz memory clock,-k phatk VECTORS BFI_INT WORKSIZE=256 AGGRESSION=13
|-
|style="background:#EFEFFF;"| 5850 || 382 || 1.8454|| || 207 || 995(OC) || 1440 || - || PCI-E 2.0 x8 || phoenix || OC 1.177v on core
|-
|style="background:#EFEFFF;"| 5850 || 391 || - || - || 180 || 725 || 1440 || 2.4 || PCI-E 2.0 x16 || Win 7 Ultimate x64 / DiabloMiner / Catalyst 12.2 || ASUS DirectCU @ GPU 960 MHz / MEM 300 Mhz @ Voltage 1.2 @ 70% FAN @ 69 temp @ Flags: -v 2,1 -w 256
|-
|style="background:#EFEFFF;"| 5850 || 391 || -|| || - || 1000 || 1440 || 2.1 || PCI-E 2.0 x16(@x8) || phoenix 1.5 / phatk / Win7 64 || Mem @ 280, fan @ 100%, Temp @ 71, 1.163 V core, -v -k phatk VECTORS BFI_INT AGGRESSION=13 FASTLOOP=false WORKSIZE=256, The name is Mautobu
|-
|style="background:#EFEFFF;"| 5850 || 392 || -||2.43 || - || 990 || 1440 || 2.4 || PCI-E 2.1 x16 || phoenix-svn (AUR) / phatk / Arch Linux || Memory: 180MHz, -v -q 1 -k phatk WORKSIZE=128 VECTORS BFI_INT AGGRESSION=13 FASTLOOP=false
|-
|style="background:#EFEFFF;"| 5850 || 397 || -|| || - || 950 || 1440 || 2.5 || PCI-E 2.1 16x || phoenix 1.5 / phatk 2.2 / Win7 64, catalyst 11.6 || Mem speed 350Mhz, Fan 85%, 70C, 1.083 Vcore, -k phatk VECTORS BFI_INT AGGRESSION=12 FASTLOOP=false WORKSIZE=256
|-
|style="background:#EFEFFF;"| 5850 || 400 || -|| || - || 1000 || 1440 || 2.4 || PCI-E 2.1 x16 || Phoenix 1.5 Win7 x64 || Memory 600MHz, Vcore 1.225, 73C, -k phatk WORKSIZE=128 VECTORS BFI_INT AGGRESSION=13 FASTLOOP=false, 3% phatk mod
|-
|style="background:#EFEFFF;"| 5850 || 404 || -|| || - || 965 || 1440 || 2.5 || PCI-E 2.0 x16(@x8) || phoenixsvn / phatk2 / Ubuntu 11.04 / catalyst 11.8 || 5870 bios flash, Mem @322, fan@55%, Temp@83oC, 1.163Vcore, -k phatk2 VECTORS BFI_INT AGGRESSION=13 FASTLOOP=false WORKSIZE=256
|-
|style="background:#EFEFFF;"| 5850 || 408 || -|| - || - || 999/275 || 1440 || 2.4 || PCI-E 2.1 x16 || phoenix 1.50 / phatk-mod / Ubuntu 10.04 || Fan 70%, temp < 60 deg C, Sapphire 5 heatpipe card, same flags as above/below (edit1- oops, no voltage tweaks... edit2- wow, phatk-mod makes a difference... catfish)
|-
|style="background:#EFEFFF;"| 5850 || 412 || -|| || - || 1010 || 1440 || 2.4 || PCI-E 2.0 1x>16x || phoenix 1.5 / phatk 3% mod / Win7 64 11.5 || VECTORS BFI_INT AGGRESSION=12 -k phatk
|-
|style="background:#EFEFFF;"| 5850 || 414.8 || -|| || - || 1018 || 450 || 2.4 || PCI-E 2.0 16x || GUIMiner / Win7 64 11.7 || I use Sapphire HD5850 Toxic 2GB and for OC TRIXX Sapphire Tweak Utility v4.0.2. 72 deg C, fan 100%, core 1018mhz, mem 450Mhz, stock voltage (1.163). proof: http://img23.imageshack.us/img23/2367/414upload.png GUIMiner parameters: -v -w256 -f1
|-
|style="background:#EFEFFF;"| 5850 || 420 || -|| || - || 1055 || 300 || 2.5 || PCI-E 2.0 1x>16x || phoenix 1.5 / phatk 3% mod / Win7 64 11.6 || Fan 80%, 66C, 1.250 Vcore, -k phatk PLATFORM=0 DEVICE=0 VECTORS BFI_INT AGGRESSION=8 And proof: http://i.imgur.com/s9hqs.png
|-
|style="background:#EFEFFF;"| 5850 || 431 || -|| || - || 1040 || 1440 || 2.4 || PCI-E 2.0 4x>16x || phoenix-svn / phatk kernel / Debian Wheezy AMD64 + fglrx 11.6 || fan 100%, vcore 1.1750 V, 72C, VECTORS BFI_INT AGGRESSION=15 FASTLOOP=false -k phatk, proof: http://imageshack.us/photo/my-images/199/431u.png/
|-
|style="background:#EFEFFF;"| 5850 || 432.15 || -|| || - || 1040 || 500 || 2.5.793.1 || PCI-E 2.0 16x || phoenix 1.7.5 / phatk2 kernel / Win7 x64 SP1 || fan 100%, vcore 1.212 V, 69C, VECTORS4 BFI_INT AGGRESSION=13 FASTLOOP=false WORKSIZE=64 -k phatk2, proof: http://dl.dropbox.com/u/18704286/mining%205850.png/ ... Card is REF HIS 5850 ... i mining at this speed for stable but... max unstable (if i play video/flashvideo it will crash) is 436.48Mhash/sec with core 1051 mem 500 vcore 1.237 (same other settings) it's too hot in VRM that not sound good to me... i don't want to kill it for my fun mining ... - Nito Niwatori
|-
|style="background:#EFEFFF;"| 5850x2 || 620 || - || || - || 800 || 1440 || 2.4 || PCI-E 2.0 x16 || Guiminer ( cl miner ) v2012-02-19 Win7 x64 || MSI OC-Edition, -v -w 128
|-
|style="background:#EFEFFF;"| 5850x2 || 702 || - || - || - || 905 (OC)|| 1440 || 2.5 || PCI-E 2.0 x16 (x2) || phoenix 2.0.0 / Win 7 x32 || ASUS DirectCU: 304Mhz Memory clock, 66% fan-speed, Voltage Tweak, AGGRESSION=13 FASTLOOP=false WORKSIZE=256 (https://www.dropbox.com/s/9u6f2jz3sz1poxb/5850.jpg)
|-
|style="background:#EFEFFF;"| 5850x2 || 720 || -|| || - || 875 (OC)|| 1440 || 2.5 || PCI-E 2.0 x16 || cgminer 2.1.2 / Win 7 x64 || 302Mhz Memory clock, 85% fan-speed, Stock Voltage, -I 6 -v 2 -w 256 (2012-02 by Swapper)
|-
|style="background:#EFEFFF;"| 5850x3 || 1,010 || -|| || - || 850 || - || 2.4 || PCI-E 2.0 (x3) || GUIMiner || -v -w128 | MSI Afterburner settings: 850MHz core clock and 500MHz memory clock
|-
|style="background:#EFEFFF;"| 5850x4 || 1360 || 1.94|| || 700@wall || 900 || || || || poclbm||
|-
|style="background:#EFEFFF;"| 5850x6 || 2,135 || -|| || - || 900 || - || 2.5 || PCI-E 2.0 (6 total, 4 full length, 2 @ PCIE1x with risers || GUIMiner 24/8/2011 - poclbm || -v -f1 -w128 | Win 7 64Bit, Gigabyte GA-890FXA-UD5 motherboard, 4gb ram, AM3 cpu, Kingston SSD, Catalyst 11.8 drivers, guiminer switches: -v -f1 -w128, MSI Afterburner settings: 900MHz core clock and 1000MHz memory clock, cable risers required to fit all 6 cards, fans 100% Proof: http://i.imgur.com/6s7zv.jpg
|-
|style="background:#EFFFEF;"| 5870M || 152.5 || -|| || - || 750(OC) || 1000 || 2.1 || PCI-E 2.1 x16 || gui-miner (win-7) ||
|-
|style="background:#EFFFEF;"| 5870M || 189.2 || -|| || - || 850(OC) || 1000 || 2.5 || PCI-E 2.1 x16 || Wins 7 64/gui-miner (win-7) || -v -w128 -f0 Graphics Overdrive setting 700->850 core clock & 900->1030memory clock . +35mhs over stock settings
|-
|style="background:#EFFFEF;"| 5870 || 313 || 1.665|| || 188 || 900? || 1600 || 2.3 || PCI-E 2.1 x16 || Diablo/Linux ||
|-
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668||1.65 || 188 || 850 || 1600 || 2.1 || PCI-E 2.1 x16 || clmine ||
|-
|style="background:#EFFFEF;"| 5870 || 340 || 1.809|| || 188 || 850 || 1600 || - || PCI-E 2.1 x16 || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]
|-
|style="background:#EFFFEF;"| 5870 || 343 || 1.824|| || 188 || 900? || 1600 || 2.1 || PCI-E 2.1 x16 || Diablo/Linux ||
|-
|style="background:#EFFFEF;"| 5870 || 355 || 1.888|| || 188 || 900? || 1600 || 2.1 || PCI-E 2.1 x16 || poclbm/Linux ||
|-
|style="background:#EFFFEF;"| 5870 || 360 || 1.6822|| || 214 || 970 || 700 || - || PCI-E 2.0 x16 || m0mchil's OpenCL w7-64 || -f 0 -v -w 128 [http://www.bitcoin.org/smf/index.php?topic=6144.msg91959#msg91959 source]
|-
|style="background:#EFFFEF;"| 5870 || 379 || 2.015|| || 188 || 850 || 1600 || - || PCI-E 2.0 x16 || hashkill-0.2.5 alpha || -D -G2
|-
|style="background:#EFFFEF;"| 5870 || 397 || -|| || - || 930 || 1600 || 2.4 || PCI-E 2.0 x16 || Phoenix 1.48 || -k phatk VECTORS BFI_INT AGGRESSION=10 WORKSIZE=128
|-
|style="background:#EFFFEF;"| 5870 || 400 || 1.9047|| || 210 || 950 || 1600 || 2.4 || PCI-E 2.0 x8 || Phoenix 1.3 || -k poclbm VECTORS AGGRESSION=7 FASTLOOP BFI_INT
|-
|style="background:#EFFFEF;"| 5870 || 408 || 1.8888|| || 216 || 980 || 1600 || 2.1 || PCI-E 2.0 x16 || poclbm/Win7x64 || -f 20 -v -w 128, BIT_ALIGN, BFI_INT
|-
|style="background:#EFFFEF;"| 5870 || 414 || 1.9255|| || 215 || 975 || 1600 || 2.4 || PCI-E 2.0 x16 || guiminer/w7x64 || -k poclbm -v -w 256 -f 1 VECTORS BITALIGN BFI_INT -- Memory Clock 300
|-
|style="background:#EFFFEF;"| 5870 || 420 || 2.0000|| || 210 || 950 || 1600 || 2.4 || PCI-E 2.0 x16 || Phoenix 1.48 || -k phatk VECTORS BFI_INT AGGRESSION=14 WORKSIZE=256 -- Memory Clock 300Mhz
|-
|style="background:#EFFFEF;"| 5870 || 421 || 1.9581|| || 215 || 975 || 1600 || 2.4 || PCI-E 2.0 x16 || Phoenix 1.47 || VECTORS BFI_INT AGGRESSION=13 -k phatk
|-
|style="background:#EFFFEF;"| 5870 || 421.5 || 2.007|| || 201 || 950 || 1600 || - || PCI-E 2.0 x16 || hashkill-0.2.5 alpha || -D -G2 (GPU OC to 900, memory downclocked to 900)
|-
|style="background:#EFFFEF;"| 5870 || 430 || || || || 980 || 1600 || 2.4 || PCI-E 2.0 x16 || Phoenix 1.48/Windows 7 64 || -k phatk VECTORS BFI_INT AGGRESSION=14 WORKSIZE=256 -- Memory Clock 300Mhz
|-
|style="background:#EFFFEF;"| 5870 || 432 || || || || 985 || 1600 || 2.4 || PCI-E 2.0 x16 || Phoenix 1.73/Windows 7 64 || -k phatk VECTORS BFI_INT AGGRESSION=11 WORKSIZE=128 Memory Clock=900Mhz Asus 76C Fan=60% 65F ambient
|-
|style="background:#EFFFEF;"| 5870 || 435 || -|| || - || 990 || 300 || 2.4 || PCI-E 2.0 x8 || LinuxCoin v0.2b phoenix/phatk || (Powercolor brand) -k phatk VECTORS BFI_INT WORKSIZE=256 AGGRESSION=11 FASTLOOPS=false
|-
|style="background:#EFFFEF;"| 5870 || 437 || || 1.90|| || 960 || - || 2.1 || PCI-E 2.0 x1 || phoenix 1.50 + phatk || Card is clocked with BIOS flash @ 960Mhz Core and 300Mhz Memory. More information and pictures: http://forum.bitcoin.org/index.php?topic=7216.msg324521#msg324521
|-
|style="background:#EFFFEF;"| 5870 || 438 || 1.9819|| || 221 || 1000(OC) || 1600 || 2.1 || PCI-E 2.0 x16 || poclbm/Linux || -v -w 64 -f 1
|-
|style="background:#EFFFEF;"| 5870 || 440 || 2.0000|| || 220 || 995 || 1600 || 2.4 || PCI-E 2.0 x16 || Phoenix ||
|-
|style="background:#EFFFEF;"| 5870 || 445 || 2.28||2.34 || 195 || 1005 || 335 || 2.4 || PCI-E 2.0 x4 || Ubuntu 11.04 phoenix/phatk || (Asus brand, volts = 1'072) -k phatk VECTORS BFI_INT WORKSIZE=256 AGGRESSION=12 FASTLOOPS=false -a 7 (-a 10)
|-
|style="background:#EFFFEF;"| 5870 || 453 || || || || 980 || 1600 || 2.5 || PCI-E 2.1 x16 || Phoenix 1.50/Windows 7 64 catalyst 11.6 phatk 2.2 || -k phatk VECTORS BFI_INT AGGRESSION=12 WORKSIZE=256 FASTLOOPS=false -- Memory Clock 350Mhz Vcore 1.163v
|-
|style="background:#EFFFEF;"| 5870 || 458 || -|| || - || 1040 || 1600 || 2.1 || PCI-E 2.0 x16 || poclbm/Windows 7 64 || -v -w 256 -f 1 Crossfired, Water cooled, 916 Mhash/s total. Best dual gpu setup me thinks? The name is Mautobu.
|-
|style="background:#EFFFEF;"| 5870 || 460 || || || || 1050 || 1600 || 2.4 || PCI-E 2.0 x16 || Guiminer || -k phatk VECTORS BFI_INT AGGRESSION=14 WORKSIZE=256 -- Memory Clock 300Mhz vcore @ 1225mV
|-
|style="background:#EFFFEF;"| 5870 || 460 || || || || 1020 || 1600 || 2.4 || PCI-E 2.0 x16 || Phoenix 1.50/Windows 7 64 || VECTORS BFI_INT AGGRESSION=12 WORKSIZE=256 -k phatk -- Memory Clock 300Mhz vcore @ 1225mV, 3% phatk mod
|-
|style="background:#EFFFEF;"| 5870 || 461 || || || || 1000 || 1600 || 2.5 || PCI-E 2.0 x16 || phoenix 1.75/Windows 7 64 || -k phatk2 (phatk 2.2) VECTORS BFI_INT AGGRESSION=9 WORKSIZE=128, Memory Clock=213, stock voltage
|-
|style="background:#EFFFEF;"| 5870 || 481 || || || || 1050 || 1600 || 2.5 || PCI-E 1x || phoenix 1.75/Windows 7 64 || -k phatk2 (phatk 2.2) VECTORS BFI_INT WORKSIZE=64 AGGRESSION=20 [MSI HD 5870 Ref Design vs Zalman VF3000A 1200mv Mem 600MHz]
|-
|style="background:#EFFFEF;"| 5870x2 (CF) || 864 || -|| || - || 900 || 3200 || 2.1 || PCI-E 2.1 x16 || guiminer || -k phatk VECTORS FASTLOOP=false AGGRESSION=7 BFI_INT WORKSIZE=128 (Same flags per GPU)
|-
|style="background:#EFFFEF;"| 5870x2 (Ares) || 620 || -|| || - || 850 || 3200 || 2.1 || PCI-E 2.1 x16 || guiminer || -v -w 128
|-
|style="background:#EFFFEF;"| 5870x2 (Ares) || 826 || 0.751|| || 1100 || 950 || 3200 || 2.1 || PCI-E 2.1 x16 || phoenix 1.4 w/ Phtak || AGGRESSION=13 WORKSIZE=128 VECTORS BFI_INT Memory @ 300MHz
|-
|style="background:#EFFFEF;"| 5870x2 (Ares) || 826 || 1.18|| || 700 || 935 || 3200 || 2.4 || PCI-E 2.1 x16 || phoenix 1.48 w/ Phatk || AGGRESSION=13 WORKSIZE=256 VECTORS BFI_INT FASTLOOP=false, memory @ 319 MHz, Windows 7 32-bit
|-
|style="background:#EFFFEF;"| 5870x2 (Ares) || 878 || 0.585|| || 1500 || 1000 || 3200 || 2.1 || PCI-E 2.1 x16 || phoenix 1.7 w/ Phtak || AGGRESSION=13 WORKSIZE=128 VECTORS BFI_INT Memory @ 300MHz
|-
|style="background:#EFFFEF;"| 5870x4 || 1784 || || 1.29|| || 960 || - || 2.1 || PCI-E 2.0 x1 || phoenix 1.50 + phatk + [https://bitcointalk.org/index.php?topic=7964.0 Version 2.2 Improvement] || Cards are clocked with BIOS flash @ 960Mhz Core and 300Mhz Memory. More information and pictures: http://forum.bitcoin.org/index.php?topic=7216.msg324521#msg324521
|-
|style="background:#EFFFEF;"| 5870x6 || 2568 || -|| || 1200 || 970 || -|| 2.4 || PCI-E 2.1 x16 || poclbm/debian32bit || -v -w128, voltage default, Mem downclocked to 300 MHz, Fan 80-90% (+ 4x12cm fun 1900rpm), Temp 6x 70-75C. Whole computer comsumpts 1280Watt. Using PCI-E risers 16x-16x to use 6 GPU cards
|-
|style="background:#FFEFEF;"| 5970 || 530 || 1.803||0.53 ? || 294 || 725 || 3200 || 2.4.595.10 || PCI-E 2.1 x16 || poclbm/201103.beta3/Windows || -v -w128 -f60
|-
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820|| || 294 || 725 || 3200 || 2.1 || PCI-E 2.1 x16 || clmine ||
|-
|style="background:#FFEFEF;"| 5970 || 560 || 1.905|| || 294 || 725 || 3200 || - || PCI-E 2.1 x16 || Diablo ||
|-
|style="background:#FFEFEF;"| 5970 || 565 || 1.922|| || 294 || 725 || 3200 || 2.1 || PCI-E 2.1 x16 || clmine2 ||
|-
|style="background:#FFEFEF;"| 5970 || 604 || 2.054|| || 294 || 725 || 3200 || 2.1 || PCI-E 2.1 x16 || clmine ||
|-
|style="background:#FFEFEF;"| 5970 || 645 || 1.875|| || 344 || 850 || 3200 || 2.1 || PCI-E 2.1 x16 || m0mchil/poclbm 03-07-11 || -f1, Debian 6, fglrx-driver 10.9.3
|-
|style="background:#FFEFEF;"| 5970 || 739 || || || || 795 || 3200 || 2.4 || PCI-E 2.1 x16 || cgminer 2.3.1 || -I 9 -k phatk -w 256 -v 2, memory clock @ 265MHz, Debian Squeeze, fglrx-driver 12.1.1, performance scales linearly with engine clock as long as memory clock is 1/3
|-
|style="background:#FFEFEF;"| 5970 || 740 || 2.1511|| || 344 || 850 || 3200 || 2.1 || PCI-E 2.1 x16 || phoenix/1.3 || AGGRESSION=12 WORKSIZE=128 VECTORS BFI_INT, memory clock @ 300MHz
|-
|style="background:#FFEFEF;"| 5970 || 755 || 2.2076|| || 342 || 848 || 3200 || 2.1 || PCI-E 2.1 x16 || poclbm 28-04-11 || -f 1 -w 256 -v, Ubuntu 10.10, fglrx 11.4, memory clock @ 300MHz
|-
|style="background:#FFEFEF;"| 5970 || 802 || 2.31|| || 347 || 850 || 3200 || 2.4 || PCI-E 2.1 x16 || phoenix poclbm Ubuntu 11.04 || -q 6 -k AGGRESSION=19 WORKSIZE=128 BFI_INT VECTORS, fglrx 11.4, mem clock @ 1000MHz
|-
|style="background:#FFEFEF;"| 5970 || 820 || ??? || || ??? || 910 || 3200 || 2.4 || PCI-E 2.1 x1 || Phoenix 1.5 Win7 || AGGRESSION=12 WORKSIZE=256 BFI_INT VECTORS -k phatk, 11.5, Mem @ 300MHz, 1.110v, 3% phatk mod
|-
|style="background:#FFEFEF;"| 5970 || 822.2 || -|| || - || 950 || 3200 || 2.4 || PCI-E 2.1 x16 || phoenix win7 || -k phatk -q 6 AGGRESSION=20 WORKSIZE=128 BFI_INT VECTORS, but with this increasing difficulty mining becomes pretty pointless
|-
|style="background:#FFEFEF;"| 5970 || 833 || -|| || - || 930 || 3200 || 2.4 || PCI-E 2.1 x16 || phoenix 1.7.5, win7 x64, catalyst 11.7 || -k phatk AGGRESSION=13 WORKSIZE=256 BFI_INT VECTORS fastloops=false. memory@300mhz, 1.125v, fan 100%, 73C core temp, 95c voltage controllers. it will clock higher but not stable without a voltage increase and i fear for the VRMs
|-
|style="background:#FFEFEF;"| 5970 || 863.4 || -|| || - || 955 || 3200 || 2.4 || PCI-E 2.1 x16 || Diablo - Debian || -v 2 -w 256 (XFX Radeon HD 5970 Black Edition)
|-
| 6310M || 9.821 || 0.545|| || 18 || 500 || 80 || 2.4 || Integrated/APU || poclbm-gui -v -w128 || HP DM1z 18W TDP is shared with the CPU
|-
| 6450 || 27.0 || 1.5 || - || 18 || 625 || 160 || 2.4 || PCI-E 2.0 x16 || guiminer/poclbm 2011-06-14 || -v -w128 Sapphire HD6450 1gb ddr3 Ubuntu 11.04 64bit
|-
| 6450 || 32.6 || 1.918 || - || 17 || 725 || 800 || 2.4 || PCI-E 2.0 x16 || guiminer/Phoenix1.75 Windows 7 x64 (no Aero)|| -k phatk VECTORS BFI_INT FASTLOOP=false AGGRESSION=11 -v WORKSIZE=64 Dell OEM HD6450 1gb ddr3 passive cooling/no fan 81C
|-
| 6450 || 37.8 || ? || - || 17 || 850 || 800 || 2.4 || PCI-E 2.0 x16 || Phoenix2.0.0 Windows 8 x64 || -k phatk2 VECTORS BFI_INT FASTLOOP=false AGGRESSION=11 -v WORKSIZE=64 Sapphire HD6450 1GB DDR3 passive cooling/no fan 150MHz memory/1000mV VCore
|-
| 6470M || 24.1 || - || ||- || - || - || 2.1 || Integrated/APU || guiminer ||
|-
| 6470M || 31.0 || - || ||- || - || - || 2.1 || Integrated/APU || phoenix 1.48 ||
|-
| 6480G || 24.1 || - || ||- || - || - || 2.1 || Integrated/APU || phoenix 1.75 ||
|-
| 6490M || 15.21 || - || ||- || - || - || - || - || [http://forum.bitcoin.org/index.php?topic=8994.0 DiabloMiner GUI] v2011-05-22 / Mac OS X 10.6.7 || Model: MacBookPro8,2 VRAM: 256MB
|-
| 6490M || 16.289 || 0.708|| || 23 || - || - || - || PCI-E 2.1 x16 || poclbm-mod (Mac OS X 10.6.7) || MacBook Pro early 2011
|-
| 6490M || 17.18 || - || ||- || - || - || - || PCI-E 2.1 x16 || phoneix 1.50 with poclbm, Mac OS X 10.6.7 || MacBook Pro 2,8 VRAM: 256MB. phoenix -k poclbm VECTORS BFI_INT FASTLOOP
|-
| 6490M || 32.1 || - || ||- || - || - || - || - || guiminer 2011-07-01 with poclbm (Win7-x64) ||MacBookPro8,2 (WinX64) -v -w128 -f0
|-
| style="background:#FFDD00;"| 6520G || 33.8 || - || || - || 400 || 320 || - || Integrated/APU || guiminer 2011-07-01 with OpenCL (Win7-64bit) || -v -w128 on Toshiba L775D-S7222
|-
|style="background:#FFDD00;"| 6530D || 40.5 || - || || - || 444 || 320 || 2.4 || FM-1 || cgminer 2.4.1 || Integrated/APU A6-3500; Linux; Catalyst 11.11; APP-SDK-v2.4 (595.10)
|-
|style="background:#FFDD00;"| 6550D(A8 Onboard) || 66.2 || -|| || - || - || - || 2.5 || FM-1 || guiminer 2011-07-01 with OpenCL (Win7-64bit) || -v -w128 -f60
|-
|style="background:#FFDD00;"| 6550D || 67.6 || -|| || - || 600 || 400 || 2.5 || FM-1 || guiminer 2011-07-01 with OpenCL (Win7-64bit) || -v -w128 -f2
|-
|style="background:#FFDD00;"| 6570 || 68.0 || 1.133|| || 60 || 650 || 480 || 2.4 || PCI-E x16 || guiminer 2011-05-21 with poclbm (Win7-32bit) || no extra option for miner . Sapphire 6570 gddr5 512mb
|-
|style="background:#FFDD00;"| 6570 || 82.1 || 1.368|| || 60 || 650 || 480 || 2.4 || PCI-E x16 || guiminer 2011-05-21 with poclbm (Win7-32bit) || -v -w128 . Sapphire 6570 gddr5 512mb
|-
|style="background:#FFDD00;"| 6570 || 86.0 || 1.95 || - || 44 || 650 || 480 || 2.4 || PCI-E x16 || guiminer/poclbm 2011-06-14 || -v -w128 Sapphire Ultimate HD6570 1gb ddr3 Ubuntu 11.04 64bit
|-
|style="background:#FFDD00;"| 6570 || 112.0 || - || || - || 860 || 480 || 2.7 || PCI-E 2.0 x16 || guiminer 2012-02-19/poclbm (Win7-64bit) || -v -w128 -f1 . Sapphire 6570 Low Profile gddr3 1024mb
|-
|style="background:#FFDD00;"| 6570 || 114.0 || - || || - || 866 || 480 || 2.7 || PCI-E 2.0 x16 || guiminer 2012-02-19/poclbm (Win7-64bit) || -v -f 0 -w128 -a 3 . XFX 6570 Full Profile gddr3 1024mb 64 bit
|-
| 6630M || 48.80 || -|| || - || - || - || - || - || [http://forum.bitcoin.org/index.php?topic=8994.0 DiabloMiner GUI] v2011-06-18 / Mac OS X 10.7 || Mac Mini 2011 MC816D/A
|-
| 6630M || 63.00 || -|| || - || 600 || 480 || 2.5 || PCI-E 2.0 x16 || DiabloMiner Windows || Lenovo ThinkPad Edge E320 (card overclocked using Sapphire TRIXX)
|-
| 6670 || 102.20 || -|| || - || 800 || - || - || PCI-E 2.1 x16 || poclbm/Debian sid || -v -f 0 -w 128
|-
| 6670 || 104.00 || - || 1.0 || - || 820 || - || - || PCI-E 2.1 x16 || guiminer(poclbm)/Win 7|| -v -a4 -f15 -d0 -w64
|-
| 6670 || 110.00 || - || 1.0 || - || 850 || - || - || PCI-E 2.1 x16 || guiminer(poclbm)/Win 7|| -v -f 0 -w 128 -q 6
|-
| 6670 || 111.77 || 1.69 || - || 66 || 910 || 480 || 2.7 || PCI-E 2.1 x16 || Phoenix 1.7.5 || -k phatk2 BFI_INT AGGRESSION=5 VECTORS WORKSIZE=128
|-
| 6670 || 120.1 || - || - || - || 900 || 480 || 2.7 || PCI-E 2.1 x16 || cgminer 2.7.4 || kernel: diablo i:10 core: 900 mem: 750
|-
| 6670 || 124.0 || - || - || 66 || 940 || 800 || 2.4 || PCI-E 2.0 x16 || Phoenix2.0.0 Windows 8 x64 || -k phatk2 VECTORS BFI_INT FASTLOOP=false AGGRESSION=11 -v WORKSIZE=128 Sapphire HD6670 Ultimate 1GB DDR5 passive cooling/no fan 300MHz memory/1100mV VCore
|-
| 6750 || 142 || -|| || 150 || 700 || - || - || PCI-E 2.1 x16 || poclbm || -v -w128, Gigabyte SL (passive cooler), watts is TDP, card runs very hot (>90°C)
|-
| 6750 || 167.59 || -|| || - || 870 || - || - || PCI-E 2.1 x16 || guiminer || -v -f30 -w128
|-
| 6750 || 172.00 || -|| || - || 860 || 600 || - || PCI-E 2.1 x16 || guiminer 2012-02-19/poclbm (Win7-64bit) MSI Afterburner 2.2.3 || -v -w128 f-20 Sapphire 6570 GDDR3 1024Mb CCC ver. 11.12 OCL 2.5
|-
| 6750M || 41.48 || -|| || - || 870 || - || - || PCI-E 2.1 x16 || diablominer ||
|-
| 6750M || 60 || -|| || - || - || - || - || - || diablominer OSX 10.7 WorkSize=128||
|-
| 6770 || 180 || -|| || - || 850 || 1200 || - || - || guiminer || -v -w128 , this was an XFX (OEM) model, GPU @ 850 MHz, mem @ 1200 MHz; I pushed it up to 190 Mhash/s briefly by overclocking, but it crashed the system above that
|-
| 6770 || 202 || -|| || - || 960 || 800 || - || PCI-E 2.1 x1,x4,x8,x16 || phoenix 1.48 || Sapphire 6770 (standard) -q2 -k poclbm DEVICE=0 AGGRESSION=10 VECTORS WORKSIZE=128 BFI_INT FASTLOOP (The PCI-E speed does not affect the mining speed)
|-
| 6770 || 217 || -|| || - || 960 || 800 || - || PCI-E x16 || Guiminer with phoenix || Sapphire 6770 -k phatk VECTORS BFI_INT WORKSIZE=128 FASTLOOP=false AGGRESSION=12 with https://forum.bitcoin.org/index.php?topic=22965.0 modification
|-
| 6770 || 221 || -|| || - || 1010 || 300 || 2.4 || PCI-E 2.0 x8 || Phoenix 1.50 || MSI 6770 -k phatk PLATFORM=0 DEVICE=0 VECTORS BFI_INT WORKSIZE=256 FASTLOOP=false AGGRESSION=13 3% Stock voltage.
|-
| 6770 || 235 || -|| || - || 1010 || 300 || 2.4 || PCI-E 2.0 x8 || Phoenix 1.50 || Sapphire 6770 -k phatk PLATFORM=0 DEVICE=0 VECTORS BFI_INT WORKSIZE=256 FASTLOOP=false AGGRESSION=13 3% mod https://forum.bitcoin.org/index.php?topic=22965.0 and AS5 paste on core w/ external 12" fan 50C full load. Stock voltage.
|-
| 6770x2 || 470 || -|| || - || 1010 || 300 || 2.4 || PCI-E 2.0 x8 || Phoenix 1.50 || Sapphire 6770 -k phatk PLATFORM=0 DEVICE=0 VECTORS BFI_INT WORKSIZE=256 FASTLOOP=false AGGRESSION=13 3% mod https://forum.bitcoin.org/index.php?topic=22965.0 and AS5 paste on core w/ external 12" fan 50C full load. Stock voltage.
|-
| 6790 || 220 || 1.467|| || 150 || 800 || - || - || PCI-E 2.1 x16 || Phoenix 1.48 || -k phatk BFI_INT FASTLOOP AGGRESSION=12 VECTORS OC'd to 1ghz, underclocked mem to 300, voltage at 1175
|-
| 6790 || 219 || 1.467|| || 150 || 960 || - || - || PCI-E 2.1 x16 || guiminer || -v -f0 -w128 / GPU OC to 960MHz under Windows7 64bit
|-
|style="background:#EFEFFF;"| 6850 || 171.59 || 1.351||1.07 || 127 || 775 || 960 || 2.1 || PCI-E 2.1 x16 || clmine ||
|-
|style="background:#EFEFFF;"| 6850 || 196 || -|| || - || 850 || 960 || - || PCI-E 2.1 x16 || poclbm || -v -w 128 -f 0
|-
|style="background:#EFEFFF;"| 6850 || 220 || 1.236(*)|| || 178(*) || 1000(OC) || 960 || 2.4RC1 || PCI-E 2.1 x16 || poclbm || -v -w 128 -f 30 (*: Overclocked wattage calculated [http://bakkap.free.fr/Misc/wCalc.html here] )
|-
|style="background:#EFEFFF;"| 6850 || 234.8 || ||- || - || 940 || 960 || 2.4 || PCI-E 2.1 x16 || Phoenix 1.3 || AGGRESSION=8 WORKSIZE=128 VECTORS BFI_INT
|-
|style="background:#EFEFFF;"| 6850 || 236.0 || ||- || - || 940 || 960 || 2.4 || PCI-E 2.1 x16 || Phoenix 1.4 || -k phatk AGGRESSION=12 WORKSIZE=128 VECTORS BFI_INT, Core @ 900MHz, Memory @ 300MHz
|-
|style="background:#EFEFFF;"| 6850 || 244.2 || ||- || - || 960 || 960 || 2.1 || PCI-E 2.0 x16 || poclbm june-2011 || -v -w 128
|-
|style="background:#EFEFFF;"| 6850 || 245.1 || ||- || 200 || 940 || 960 || 2.4 || PCI-E 2.0 x16 || guiminer (Phoenix) || Sapphire 6850 (Memory @1000MHz); Win7 64bit; flags: -k phatk VECTORS BFI_INT FASTLOOP=false AGGRESSION=14 WORKSIZE=128
|-
|style="background:#EFEFFF;"| 6850 || 250 || 1.612(*) ||- || 155(*) || 940 (OC) || 960 || 2.4 || PCI-E 2.0 x16 || AOCLBF 1.74 (Phoenix 1.5**) @Win7/x64 || XFX 6850 (Memory @840MHz; Vdcc @1.148V; Fan @74%; Temp @70C; System @39C); flags: -k phatk BFI_INT FASTLOOP VECTORS AGGRESSION=11 WORKSIZE=128 (*: Overclocked wattage calculated [http://bakkap.free.fr/Misc/wCalc.html here] / **: [http://forum.bitcoin.org/index.php?topic=22965.0 Tainted Kernel])
|-
|style="background:#EFEFFF;"| 6850 || 256.2 || || - || 170 || 980 || 960 || 2.7 || PCI-E 2.0 x16 || phoenix 1.7.5 / Win7 32bit || -k phatk -VECTORS BFI_INT AGGRESSION=9, Sapphire VaporX 1GB, mem@250MHz, stock VDDC 1.150V
|-
|style="background:#EFEFFF;"| 6850 || 262.5 || || - || - || 965 || 525 || 2.4 || PCI-E 2.0 x16 || guiminer / poclbm || -v -f 0 -w 128 (HIS 6850 flashed to HIS 6870 BIOS)
|-
|style="background:#EFEFFF;"| 6850 || 267.2 || ||1.67 || - || 1010(OC) || 960 || 2.4 || PCI-E 2.0 x16 || guiminer / phoenix 1.50 || -k phatk VECTORS BFI_INT AGGRESSION=11 worksize=128 FASTLOOP=false
|-
|style="background:#EFEFFF;"| 6850 || 301.4 || ||1.67 || - || || || 2.4 || PCI-E 2.0 x16 || guiminer / poclbm || -v -f 2 -w 128 clock @ 985 mem @ 890
|-
|style="background:#FFFF00;"| 6870 || 232.47 || 1.540||1.22 || 151 || 900 || 1120 || - || PCI-E 2.1 x16 || poclbm -v -w 128 ||
|-
|style="background:#FFFF00;"| 6870 || 245|| -|| || - || 900|| 1120 || 2.4 || PCI-E 2.0 x16 || ph rising 1.45 phoenix 1.50 phatk 11.5 sdk 2.4 || HD5xxx+ Fastloop phatk AGGRESSION=10
|-
|style="background:#FFFF00;"| 6870 || 264.5 || - || - || - || 980 || 1050 || - || PCI-E 2.1 x16 || GUIMiner v2011-05-01 || Stays around 66*C if I keep the side panel off and the room well ventilated. Card is PowerColor branded. Windows 7 Ultimate SP1 with Classic theme. Fan is at 100%. -v -w128
|-
|style="background:#FFFF00;"| 6870 || 271 || 1.807|| || 150 || 940 || 1120|| 2.4 || PCI-E 2.0 x16 || poclbm -v -w 128 || Debian 6.0.1 x86_64
|-
|style="background:#FFFF00;"| 6870 || 277.47 || -|| || - || 940 || 1120 || - || PCI-E 2.1 x16 || Phoenix 1.3 || AGGRESSION=8 WORKSIZE=128 VECTORS BFI_INT
|-
|style="background:#FFFF00;"| 6870 || 279 || 1.847(?)|| || 151(?) || 900 || 1120 || 2.4 || PCI-E 2.1 x16 || hashkill-0.2.5 alpha cat 11.4 sdk 2.4 || -G2 -D stock clocks, debian linux 64bit
|-
|style="background:#FFFF00;"| 6870 || 281.7 || 1.172 (stock)|| || - || 980 || 1120|| 2.4 || PCI-E 2.1 x16 || guiminer-v2011-06-09 || xfx6870, flags: -v 19 -w 128, win7 32-bit
|-
|style="background:#FFFF00;"| 6870 || 293.13 || || ||- || 945 || 1050|| 2.5 || PCI-E 2.1 x16 || Phoenix 1.5 Phatk || xfx6870, Catalyst 11.6, 1.5 Phoenix flags: -k phatk FASTLOOP=false DEVICE=0 VECTORS BFI_INT AGGRESSION=13 WORKSIZE=128; http://forum.bitcoin.org/index.php?topic=25860.0 Kernel Patch; http://forum.bitcoin.org/index.php?topic=6458.0 Cmd; http://developer.amd.com/tools/gDEBugger/Pages/default.aspx No Crossfire Required; runs faster without crossfire 1% + additional 3% from update
|-
|style="background:#FFFF00;"| 6870 || 294 || || ||- || 980 || 1120|| 2.4 || PCI-E 2.1 x16 || phoenix phatk || xfx6870, 340MHz memory clock, Catalyst 11.6, flags: BFI_INT VECTORS AGGRESSION=9 WORKSIZE=256
|-
|style="background:#FFFF00;"| 6870 || 294 || || ||- || 985 || 1100|| 2.4 || PCI-E 2.0 x8 || Diablo || Powercolor branded card, Win 8 x64, -v 1 -w 256
|-
|style="background:#FFFF00;"| 6870 || 295 || 2.02||1.64 || 146 || 950 || 1120 || 2.4 || PCI-E 2.1 x16 || hashkill latest as of 7/6/11 (ubuntu 11.4) || hashkill-gpu -p bitcoin user:pass:server -D, mem clock 850, voltage @ 1.175, Fan @ 70%, Temp @ 71C.
|-
|style="background:#FFFF00;"| 6870 || 297|| -|| || - || 1000|| 1120 || 2.4 || PCI-E 2.0 x16 || ph rising 1.62 phoenix 1.50 phatk 11.5 sdk 2.4 || Vectors HD5xxx+ Fastloop phatk AGGRESSION=11 WORKSIZE=128
|-
|style="background:#FFFF00;"| 6870 || 300 || - || || - || 940 || 1120 || 2.5 || PCI-E 2.1 x16 || Phoenix 1.6.2 phatk2 || xfx6870 Black Edition, 340MHz Memory Clock, Catalyst 11.6, VECTORS BFI_INT AGGRESSION=13 WORKSIZE=128, Debian Linux 64-Bit, Fan @ 50%, Temp @ 75C
|-
|style="background:#FFFF00;"| 6870 || 300 || 1.72 || - || 174 || 1038 || 1120 || 2.4 || PCI-E 2.1 x16 || poclbm windows7x86 cat 11.4 || -v -w128 -f1 mem clock 360, fan 100% temp 73C
|-
|style="background:#FFFF00;"| 6870 || 300.06 || 1.830|| || 164 || 1020 || 1120 || 2.4 || PCI-E 2.1 x16 || Phoenix 1.4 cat 11.4 || VECTORS BFI_INT AGGRESSION=8 fastloop mem clock 344
|-
|style="background:#FFFF00;"| 6870 || 302 || - || || - || 940 || 1120 || 2.5 || PCI-E 2.1 x16 || cgminer 2.1.2 || xfx6870 Black Edition, 340MHz Memory Clock, Catalyst 11.6, -w 256 -I 9, Debian Linux 64-Bit, Fan @ 50%, Temp @ 75C
|-
|style="background:#FFFF00;"| 6870 || 307 || 1.72 || - || 174 || 1001/\1001 || 1120 || 2.4 || PCI-E 2.1 x16 || poclbm windows7x86 cat11.8 || -v -w128 -f5,85°C
|-
|style="background:#FFFF00;"| 6870 || 310 || - || - || - || 1000 || 1120 || || PCI-E 2.1 x16 || cgminer 3.1.0 (Ubuntu Server 12.04 LTS AMD64) || intensity=13, vectors=2, worksize=128, kernel=diablo, gpu-engine=1000, gpu-memclock=900
|-
|style="background:#FFFF00;"| 6870 || 310 || - || - || - || 1035 || 1120 || 2.4 || PCI-E 2.1 x16 || phoenix 1.48 phatk 11.5 sdk 2.4 || BFI_INT VECTORS FASTLOOP=false AGGRESSION=12 WORKSIZE=128, mem clock @ 300MHz, voltage @ 1.300
|-
|style="background:#FFFF00;"| 6870 || 310 || -|| || - || 975 || 1120 || 2.4 || PCI-E 2.1 x16 || phoenix phatk linuxcoin || BFI_INT VECTORS FASTLOOP=false AGGRESSION=13 WORKSIZE=128, mem clock @ 340MHz, core clock @ 970MHz, flashed bios, 72 degrees w/ fan @ 68%, GIGABYTE SOC
|-
|style="background:#FFFF00;"| 6870 || 312 || -|| || - || 975 || 300|| 2.4 || PCI-E 2.1 x16 || phoenix 1.50 / phatk / Windows 7 x64 SP1 || VECTORS BFI_INT AGGRESSION=11 FASTLOOP=false WORKSIZE=256, mem clock @ 300MHz, voltage @ 1.300, Fan @ 45%, Temp @ 62C, MSI 6870 HAWK.
|-
|style="background:#FFFF00;"| 6870 || 314 || -|| || - || 1030 || 1120|| 2.4 || PCI-E 2.1 x16 || phoenix 1.50 / phatk / Linux || VECTORS BFI_INT AGGRESSION=11 FASTLOOP=false WORKSIZE=256
|-
|style="background:#FFFF00;"| 6870 || 316 || -|| || - || 1030 || 1120 || 2.4 || PCI-E 2.1 x16 || guiminer 2011-06-09 using phoenix (Win7-32bit) || -k phatk platform=0 device=0 VECTORS BFI_INT AGGRESSION=11 worksize=128 FASTLOOP=false, mem clock @ 228MHz, voltage @ 1.25, Fan @ 40%, Temp @ 73C
|-
|style="background:#FFFF00;"| 6870 || 320 || - || - || 160 || 950 || 1120 || 2.4 || PCI-E 2.0 x16 || Win 7 Ultimate x64 / DiabloMiner / Catalyst 12.1 || Saphire @ GPU 1030 MHz / MEM 300 Mhz @ Voltage 1.25 @ 80% FAN @ 69 temp @ Flags: -v 2 -w 128
|-
|style="background:#FFFF00;"| 6870 || 321|| -|| || - || 1050|| 1120 || 2.4 || PCI-E 2.1 x8 ||aoclbf 1.7 phoenix 1.50 11.6|| Vectors HD5xxx+ phatk AGGRESSION=13 WORKSIZE=256, Memory=325MHz, Volts=1.3V, Fan~55%, Temps~70C
|-
|style="background:#FFFF00;"| 6870 || 322 || 1.882|| || 170 || 1050 || 1120 || 2.4 || PCI-E 2.1 x16 || phoenix 1.47 phatk 11.5 sdk 2.4 || BFI_INT VECTORS FASTLOOP=false AGGRESSION=12 WORKSIZE=256, mem clock @ 400MHz
|-
|style="background:#FFFF00;"| 6870 || 329 || -|| || - || 1075 || 1120|| 2.4 || PCI-E 2.1 x16 || phoenix 1.48 phatk 11.5 sdk 2.4 || BFI_INT VECTORS FASTLOOP=false AGGRESSION=11 WORKSIZE=256
|-
|style="background:#FFFF00;"| 6870 || 332 || -||1.74 || - || 1050 || 1120 || 2.4 || PCI-E 2.1 x16 || guiminer 2011-06-14 using phoenix (Win7-32bit) || -k phatk platform=0 device=0 VECTORS BFI_INT AGGRESSION=13 worksize=128 FASTLOOP=false, mem clock @ 228MHz, voltage @ 1.3, Fan @ 60%, Temp @ 74C, flash and browser hardware acceleration disabled, aero enabled.
|-
|style="background:#FFFF00;"| 6870 || 339.25 || - || - || - || 1090 || 1120 || 2.6 || PCI-E 2.1 x16 || Phoenix 1.7.3 cat 12.1 || Mem @ 350Mhz Clock @ 1090 Voltage 1.337 fan @ 100 Temp @ 75 diapolo's modified phatk kernel -k phatk_dia platform=0 device=0 VECTORS2 AGGRESSION=11 worksize=64 FASTLOOP=false BFI_INT
|-
|style="background:#FFFF00;"| 6870 || 375 || - || - || - || 1000 || 1120 || 2.5 || PCI-E 2.0 x16 || Win 7 Ultimate 32-bit / Guiminer v2011-07-01 / phoenix 1.5 / phatk2 / Catalyst 11.9 || XFX / GPU @ 1000 MHz / MEM @ 200 Mhz / Voltage @ 1.187 V / FAN @ 40% / Temp @ 72 C / Flags: -k phatk2 platform=0 device=0 VECTORS BFI_INT AGGRESSION=6 worksize=128 FASTLOOP=false / Using 2 miners with equal settings on 1 GPU
|-
|style="background:#FFFF00;"| 6870x2 || 600 || - || - || - || 945 || 330 || 2.5 || PCI-E 2.0 x16 || Ubuntu 12.04 32-bit / Phoenix 2 / phatk2 / Catalyst 11.9 || XFX / GPU @ 945 MHz / MEM @ 330 Mhz / Voltage @ 1.175 / Config: phatk2 VECTORS4 BFI_INT AGGRESSION=12 worksize=128 FASTLOOP=false GOFFSET=True
|-
|style="background:#FFFF00;"| 6870x4 || 1150|| -|| 1.2 || - || 900|| 1050 || 2.4 || PCI-E 2.0 x16 || phoenix 1.7 (Win7-64bit) || -k phatk platform=0 device=0-3 VECTORS BFI_INT AGGRESSION=11 worksize=128 FASTLOOP=false
|-
|style="background:#FFFF00;"| 6870x4 || 1180 || -|| - || 145 || 950 || 1120 || 2.4 || PCI-E 2.1 x16 || poclbm/debian32bit || -v -w128, Gigabyte SOC. voltage 1.175 (default), GPU default 950 MHz, Mem downclocked to 300 MHz, Fan 4x100% (+ 2x12cm fun 1300rpm), Temp 4x75C (in summer).
|-
|style="background:#FFFF00;"| 6870x4 || 1200 || -|| - || 150 || 970 || 1120 || 2.4 || PCI-E 2.1 x16 || poclbm/debian32bit || -v -w128, Gigabyte SOC. voltage 1.175 (default), GPU overclocked from 950 to 970 MHz, Mem downclocked to 300 MHz, Fan 4x100% (+ 2x12cm fun 1300rpm), Temp 4x75C (in summer). Unstable with GPU@975 MHz.
|-
| 6930 || 320|| -|| - || - || 960 || 1200 || 2.1 || PCI-E 2.1 x16 || phoenix 1.75/phatk || stock voltage, BFI_INT FASTLOOP VECTORS AGGRESSION=13 WORKSIZE=64. 70C, FAN 80% (HIS brand)
|-
| 6930 || 370|| -|| - || - || 980 || 855 || 2.4 || PCI-E 2.1 x16 || cgminer-2.4.1 || stock voltage (1,160), -I9. 71C, FAN 85% (HIS brand)
|-
| 6930 || 372 || -||1.89(?) || - || 1000 || 900 || 2.4 || PCI-E 2.1 x16 || phoenix 1.75/poclbm || max stable @ 1200 mV, BFI_INT FASTLOOP VECTORS AGGRESSION=13 WORKSIZE=64
|-
| style="background:#00FFFF;"|6930x2|| 700 ||- || - ||400~|| 940 || 2560 || 2.4 || PCI-E 2.1 x16 || Guiminer || max stable @ 1100mV mem 300, Fan 80-90%, temp 70-75, -v -w64 -f10
|-
| 6950 || 272 || -||0.90 || - || 900 || 1408 || 2.4 || PCI-E 2.1 x16 || phoenix 1.48/poclbm || max stable @ 1150 mV, AGGRESSION = 7, BFI_INT, MSI 6950
|-
| 6950 || 291 || -|| || - || 920 || 1408 || 2.4 || PCI-E 2.1 x16 || phoenix 1.48/poclbm || max stable @ 1200mV, AGGRESSION = 7, BFI_INT, MSI 6950
|-
| 6950 || 295 || -|| || - || 930 || 1408 || 2.4 || PCI-E 2.1 x16 || phoenix 1.48/poclbm || max stable @ 1275mV, AGGRESSION = 7, BFI_INT, MSI 6950
|-
| 6950 || 295 || 1.844(?)|| || 160(?) || 810 || 1536 || 2.4.595.0 || PCI-E 2.1 x16 || m0mchil/poclbm 03-07-11 || unlocked shaders, default mem 1250
|-
| 6950 || 300 || -|| || - || 940 || 1408 || 2.4 || PCI-E 2.1 x16 || phoenix 1.48/poclbm || max stable @ 1300mV, AGGRESSION = 7, BFI_INT, MSI 6950
|-
| 6950 || 314 || -|| || - || 800 || 1408 || 2.4.595.0 || PCI-E 2.1 x16 || guiminer/poclbm 05-01-11 || -v -f30 -w128 default mem 1250 Stock Sapphire 6950 1gb
|-
| 6950 || 325 || 1.635(?)|| || 200(?) || 885 || 1536 || 2.4.595.0 || PCI-E 2.1 x16 || m0mchil/poclbm 03-07-11 || unlocked shaders, default mem 1250
|-
| 6950 || 332 || 1.95~ || 1.2~ || 170~ || 840 || 1408 || 2.5.684.212 || PCI-E 2.1 x16 || guiminer/poclbm 2011-06-14 || -v -w 128 -f 0, WinXP x86, Cat11.6b, desktop on IGP, Sapphire 1GB w/ HW locked BIOS, +40MHz GPU OC, 160W ACP + 5% OC = 170W new estimated ACP
|-
| 6950 || 333 || 1.95~ || 1.2~ || 170~ || 840 || 1408 || 2.4.650.9 || PCI-E 2.1 x16 || guiminer/poclbm 2011-06-14 || -v -w 128 -f 0, WinXP x86, Cat11.6, desktop on IGP, Sapphire 1GB w/ HW locked BIOS, +40MHz GPU OC, 160W ACP + 5% OC = 170W new estimated ACP
|-
| 6950 || 338 || 1.84~ || - || 184~ || 860 || 1408 || 2.4 || PCI-E 2.1 x16 || Phoenix 1.50/poclbm kernel || Sapphire 2GB card w/ HW locked BIOS; Cat 11.6, Win7 x64; core @ 860MHz & 1087mV (OC + undervolt), mem @ 860MHz; cmd line args: VECTORS BFI_INT AGGRESSION=11 WORKSIZE=128; power and MH/J calculated using Power = C*f*v^2 w/ assumption of 175 W at stock settings w/ 100% GPU util. (not measured)
|-
| 6950 || 340 || - || ||- || 895 || 1408 || 2.4 || PCI-E 2.1 x16 || guiminer/poclbm 05-21-11 || -v -w 128, mem @ 500, 1200 mV, MSI 6950
|-
| 6950 || 340 || - || ||- || 800 || 1536 ||(?) || PCI-E 2.1 x16 || guiminer/poclbm 05-21-11 || -v -f30 -w128 default mem 1250,Sapphire 6950 1gb, unlocked shaders
|-
| 6950 || 343 || 2.14 || - || 160 || 840 || 1536 || 2.4 || PCI-E 2.1 x16 || phoenix 06-27-11 || VECTORS BFI_INT AGGRESSION=11 WORKSIZE=128 FASTLOOP=false, HIS H695FN2G2M 2GB, mem @ 720, Kill-a-Watt measured
|-
| 6950 || 344 || 2.02~ || 1.27~ || 170~ || 840 || 1408 || 2.5.684.212 || PCI-E 2.1 x16 || poclbm/20110709 || -v -w 128 -f 0, WinXP x86, Cat11.6b, desktop on IGP, Sapphire 1GB w/ HW locked BIOS, +40MHz GPU OC, 160W ACP + 5% OC = 170W new estimated ACP
|-
| 6950 || 344.4 || -|| || - || 800 || 1536 || - || PCI-E 2.1 x16 || guiminer/poclbm || Powercolor 6950 @ shadermod on original Bios 6950 / 1000mV 850/730, +20% powertune, Fan @ 60%, -v -w128 -f1.
|-
| 6950 || 349 || 1.745(?)|| || 200(?) || 800 || 1408 || - || PCI-E 2.1 x16 || guiminer/poclbm 05-21-11 || -v -f30 -w128, xfx 6950 xxx 1gb, locked shaders, core 900, mem 650, 79° C
|-
| 6950 || 351 || 1.91~ || - || 184~ || 860 || 1408 || 2.4 || PCI-E 2.1 x16 || GUIminer/poclbm v2011-07-01 || Sapphire 2GB card w/ HW locked BIOS; Cat 11.6, Win7 x64; core @ 860MHz & 1087mV (OC + undervolt), mem @ 860MHz; cmd line args: -v -w 128 -f 0; (same system as the 338 MH/s result above using Phoenix)
|-
| 6950 || 352.8 || -|| || - || 820 || 1536 || - || PCI-E 2.1 x16 || guiminer/poclbm || Powercolor 6950 @ shadermod on original Bios 6950 / 1000mV 850/730, +20% powertune, Fan @ 60%, -v -w128 -f1.
|-
| 6950 || 360 || 1.8(?)|| || 200(?) || 970 || 1536 || 2.4.595.0 || PCI-E 2.1 x16 || m0mchil/poclbm 03-07-11 || unlocked shaders, default mem 1250
|-
| 6950 || 360 || -|| || - || 870 || 1375 || - || PCI-E 2.1 x16 || guiminer/poclbm || flashed with 6970 BIOS, -v -f30 -w128
|-
| 6950 || 365 || -|| || - || 925 || 1408 || - || PCI-E 2.1 x16 || guiminer/poclbm || stock bios, -v -f0 -w128, MSI twinfrozr III 2GB
|-
| 6950 || 366.4 || -|| || - || 850 || 1536 || - || PCI-E 2.1 x16 || guiminer/poclbm || Powercolor 6950 @ shadermod on original Bios 6950 / 1000mV 850/730, +20% powertune, Fan @ 60%, -v -w128 -f1.
|-
| 6950 || 381 || -|| || - || 850 || 1536 || - || PCI-E 2.1 x16 || cgminer/phatk || XFX 6950 2Gb reference @ shadermod on original Bios 6950 / 1100mV 850/1250, +10% powertune, I=5, Fan @ 54% ~3100RPM, temp 73C w128. Windows7x64, Catalyst 13.1 .
|-
| 6950 || 383 || -|| || - || 975 || 1408 || - || PCI-E 2.1 x16 || guiminer/poclbm || stock bios, -v -f0 -w128, voltage 1.274 @72c MSI twinfrozr III 2GB
|-
| 6950 || 388.4 || -|| || - || 900 || 1536 || - || PCI-E 2.1 x16 || guiminer/poclbm || Powercolor 6950 @ shadermod on original Bios 6950 / 1000mV 850/730, +20% powertune, Fan @ 60%, -v -w128 -f1.
|-
| 6950 || 389.9 || -|| || - || 950 || 1408 || - || PCI-E 2.0 x16 || cgminer 2.3.2/Diablo || stock bios, -I 9, VRAM @ 820Mhz, fan @ 100%, voltage 1.250v, temp @ 68c, HIS ICE-Q X 2GB, OCed using MSI Afterburner, Windows 7 Professional 64-bit SP 1
|-
| 6950 || 400~ || -|| || - || 895 || 320 || 1536|| PCI-E 2.1 x16 || GUIMiner 24th Aug 2011 || Sapphire HD6950 Shader unlock mod 1408>1536 / +20% Power control, Fan @ 55%, Flags:-v -f2 -w64 -r5.Note this keeps temps under 80oC which is needed for this to be stable.Moderate fan noise.Power use is ~200W.
|-
| 6950 || 403 || -|| || - || 939 || 685 || - || PCI-E 2.1 x16 || phoenix-1.50/phatk || ASUS EAH6950 ([http://www.techpowerup.com/vgabios/90661/Asus.HD6970.2048.101124.html (Ref. 6950 Flashed -> 6970)]) / +10% overdrive volt., Fan @ 90%, VECTORS BFI_INT WORKSIZE=128 AGGRESSION=13. Overclocked from 880 -> 939 with MSI Aferburner
|-
| 6950 || 408.8 || -|| || - || 925 || 1536 || - || PCI-E 2.0 x16 || cgminer 2.12 || GIGABYTE GV-R695D5-2GD-B @ shadermod on original Bios 6950, mem@625, V=1100mv Fan @ 60%. Windows 7x64, Catalyst 11.9
|-
| 6950 || 410.4 || -|| || - || 950 || 1536 || - || PCI-E 2.1 x16 || guiminer/poclbm || Powercolor 6950 @ shadermod on original Bios 6950 / 1000mV 850/730, +20% powertune, Fan @ 60%, -v -w128 -f1.
|-
| 6950 || 417 || 2.085(?)|| || 200(?) || 975 || 1536 || 2.4.595.0 || PCI-E 2.1 x16 || guiminer/poclbm || unlocked shaders, +20% overdrive, mem @ 1250, fan @ 77%, temp 64C, -v -w128, gpu core @ 1145mV
|-
| 6950 || 418.8 || -|| || - || 940|| 1536 || - || PCI-E 2.1 x16 || guiminer/poclbm || Gigabyte OC 1GB, shadermod, voltage locked 1.175, mem 450, -w128 -v -f0, ATI Tray Tool
|-
| 6950 || 425.3 || -|| || - || 950/850 || 1536 || - || PCI-E 2.1 x16 || phoenix-1.50/phatk2 (Ubuntu natty) || Asus 1GB DirectCU, shadermod on OEM BIOS, OEM 1.1v, AMDOverdriveCtrl for 950 core 850 mem, 20% overdrive, flags VECTORS2 BFI_INT FASTLOOP=false AGGRESSION=13 WORKSIZE=128
|-
| 6950 || 428 || 2.14(?)|| || 200(?) || 1000 || 1536 || 2.4.595.0 || PCI-E 2.1 x16 || guiminer/poclbm || unlocked shaders, +20% overdrive, mem @ 1250, fan @ 80%, temp 64C, -v -w128, gpu core @ 1160mV
|-
| 6950 || 432 || 2.16(?)||1.44 || 200(?) || 1000 || 1536 || 2.4.595.0 || PCI-E 2.1 x16 || guiminer/poclbm || unlocked shaders, +20% overdrive, mem @ 520, fan @ 80%, temp 76C, -v -w128 -f 2, gpu core @ 1275mV
|-
| 6950 || 432.4 || -|| || - || 1000 || 1536 || - || PCI-E 2.1 x16 || guiminer/poclbm || Powercolor 6950 @ shadermod on original Bios 6950 / 1000mV 850/730, +20% powertune, Fan @ 60%, -v -w128 -f1.
|-
| 6950 || 440 || || || || 990 || 1536 || 2.4 || PCI-E 2.1 x16 || guiminer/phatk || unlocked shaders, mem @ 1375, VGPU 1.21v, Watercooled (MCW60), temp 54C, VECTORS BFI_INT AGGRESSION=11 -k phatk
|-
| 6950 || 454.4 || -|| || - || 1050 || 1536 || - || PCI-E 2.1 x16 || guiminer/poclbm || Powercolor 6950 @ shadermod on original Bios 6950 / 1000mV 850/730, +20% powertune, Fan @ 60%, -v -w128 -f1.
|-
|style="background:#FFAFAF;"| 6950x2 CF || 720 || - || - || 400 ~|| 900 || 1408 || 2.4.595.0 || PCI-E 2.1 x16 || GUIMiner v2011-07-01 || MSI Afterburner - gpu @ 900 (870 stock), mem @ 900 (1250 stock), temp 69-71C(bottom vga) fan@94% / 77-81C(top vga) fan@99% - 31C enviornment, -v -f 1 -w 128 BFI_INT
|-
|style="background:#FFAFAF;"| 6950x2 CF || 731 || - || - || 400~ || 900 || 1408 || 2.4.595.0 || PCI-E 2.1 x16 || GUIMiner v2011-07-01 || MSI Afterburner - gpu @ 900 (870 stock), mem @ 900 (1250 stock), temp 68C(bottom vga) fan@90% / 73C(top vga) fan@99% - 28C enviornment, -v -f 1 -w 128 BFI_INT AGGRESSION=13
|-
| 6950x3 || 1081 || -|| || - || 860 || 1408 || 2.4(?) || PCI-E 2.1 x8 || guiminer/poclbm 07-01 || Sapphire 2GB stock bios, stock voltage, locked shaders: +20% overdrive, mem@650, fan@95%, temp 94C, -v -f0 -w128, 93c
|-
| 6950x4 || 1316 || 1.513|| || 870 || 840 || 1408 || 2.4.595.0 || PCI-E 2.1 x16 || m0mchil/poclbm 03-07-11 || locked shaders, default mem 1250, dual fan 75C typical
|-
|style="background:#F0FF0F;"| 6970 || 323 || 1.468||0.92 || 220 || 880 || 1536 || 2.3 || PCI-E 2.1 x16 || poclbm || -w 64, SDK 2.1 not supported on 69xx.
|-
|style="background:#F0FF0F;"| 6970 || 365 || 2.28|| || 160 || 880 || 1536 || 2.5 || PCI-E 2.1 x16 || guiminer/phoenix || VECTORS AGGRESSION=9 WORKSIZE=128, fan @ 45%, 61C, 1.0 Vcore, 150 MHz mem, TX650w (84%), reference card
|-
|style="background:#F0FF0F;"| 6970 || 370 || -|| || - || 880 || 1536 || 2.4 || PCI-E 2.1 x16 || guiminer/poclbm || -v -w128, fan @ 50%/temp 72C, stock card
|-
|style="background:#F0FF0F;"| 6970 || 372 || 1.691(?)|| || 220(?) || 900 || 1536 || 2.4 || PCI-E 2.1 x16 || phoenix (svn trunk 05.14.2011) || clock 900/1375, VECTORS BFI_INT AGGRESSION=11 WORKSIZE=128, fan 45% (auto) / temp 90C
|-
|style="background:#F0FF0F;"| 6970 || 380 || -|| || - || - || - || 2.4 || PCI-E 2.1 x16 || poclbm || -v -w128 export GPU_USE_SYNC_OBJECTS=1 # to reduce poclbm CPU from 100% to 2%
|-
|style="background:#F0FF0F;"| 6970 || 385 || 1.964|| || 196 || 900 || 1536 || 2.4 || PCI-E 2.1 x16 || guiminer/poclbm || -v -w128, memory downclocked to 684Mhz, fan @ 70%/temp 81C
|-
|style="background:#F0FF0F;"| 6970 || 388 || -|| || - || 900 || 1536 || 2.4 || PCI-E 2.1 x16 || guiminer/poclbm || -v -w128, fan @ 50%/temp 72C, stock voltage of 1.175v
|-
|style="background:#F0FF0F;"| 6970 || 403 || -|| || - || MAX || 1536 || 2.4 || PCI-E 2.1 x16 || guiminer/poclbm || clock Max/50%+stock, -v -w128, fan= 100%/temp 72C (Note: Overclocked using CCC utility under Windows 7, Clock set to Max value w/ 50% increase to memory and 5% increase to voltage)
|-
|style="background:#F0FF0F;"| 6970 || 406 || -|| || - || 950 || 1536 || 2.4 || PCI-E 2.1 x16 || phoenix 1.50/phatk || GPU Overclocked to Max (950MHz) using aticonfig, Memory Underclocked using AMDOverdriveCtrl (850MHz). Temp ~ 82C. VECTORS BFI_INT FASTLOOP=false AGGRESSION=11 WORKSIZE=128
|-
|style="background:#F0FF0F;"| 6970 || 407 || -|| || - || 955 || 1536 || 2.4 || PCI-E 2.1 x16 || poclbm || -v -w128, fan 75%/temp 75C, voltage +10%
|-
|style="background:#F0FF0F;"| 6970 || 414 || -|| || - || 960 || 1536 || 2.4 || PCI-E 2.1 x16 || guiminer/poclbm || -v -w128, fan @ 53%/temp 73C, stock voltage of 1.175v, high air flow case
|-
|style="background:#F0FF0F;"| 6970 || 420 || -|| || - || 975 || 1536 || 2.4 || PCI-E 2.1 x16 || guiminer/poclbm || -v -w128 -f0, clocks 975MHz/685MHz MSI Lightning
|-
|style="background:#F0FF0F;"| 6970 || 423 || -||1.20 || - || 995 || 1536 || 2.4 || PCI-E 2.1 x16 || phoenix 1.48/poclbm || ATI Tray Tools, Clocks=995/331.25, WORKSIZE=128 BFI_INT AGGRESSION=11 VECTORS ,68C @ 65% Fan, HAF932 Case
|-
|style="background:#F0FF0F;"| 6970 || 431 || -|| - || - || 976 || 1536 || 2.4 || PCI-E 2.1 x16 || phoenix 1.7/phatk2 || MSI AFTERBURNER, Clocks[976/1000], -k parameters[VECTORS BFI_INT AGGRESSION=11], Temperatures{CARD}[86C@100% Fan]{ROOM}[27C/81F],
|-
|style="background:#F0FF0F;"| 6970 || 433 || -|| - || - || 975 || 1536 || 2.6 || PCI-E 2.1 x16 || phoenix 1.6.2/phatk || MSI Afterburner 2.2Beta, -k phatk AGGRESSION=11 WORKSIZE=128 VECTORS, GPU 65C@100% Fan, Room 21C
|-
|style="background:#F0FF0F;"| 6970x2 || 710 || -|| || - || 900/880 || 1536 || 2.2 || PCI-E 2.1 x16 || poclbm || -w 256
|-
|style="background:#F0FF0F;"| 6970x2 || 828|| -|| || - || 940 || 1536 || 2.4 || PCI-E 2.1 x16 || poclbm || -v -w128, fans 74%/82%, temp 74C/82C, powertune +20% (via CCC), memory underclock 825MHz (via MSI Afterburner), with 'Maj' fix
|-
|style="background:#F0FF0F;"| 6970x3 || 1243|| -|| || 1000+ || 910 || 1536 || 2.5 || 2x16, 1x8 || phoenix 1.7.0 || fans 100%, temp 88C/84C/69C, GPU 920/ memory 795/ powertune 20%, ATI 11.11, -k phatk2 VECTORS BFI_INT FASTLOOP=false WORKSIZE=128 AGGRESSION=13
|-
| 6990 || 670 || 1.94||0.89 || 346 || 830 || 3072 || 2.4 || PCI-E 2.1 x16 || poclbm || Catalyst 11.4 [http://forum.bitcoin.org/index.php?topic=2949.msg106238#msg106238 source].
|-
| 6990 || 704 || || || || 830 || 3072 || 2.4 || PCI-E 2.1 x16 || Diablo Win7 64bits || Catalyst 11.4, Arguments: -v 2 -w 128 (by Swapper 2011-07-07)
|-
| 6990 || 708 || 2.05|| || 346 || 830 || 3072 || 2.3 || PCI-E 2.1 x16 || mrb's hdminer || BIOS switch at "default" position 2, see [http://www.bitcoin.org/smf/index.php?topic=2949 source]
|-
| 6990 || 744 || || || || 830 || 3072 || 2.5 || PCI-E 2.1 x16 || Diablo Win7 64bits || Catalyst 11.6b, Arguments: -v 2 -w 128 (by Swapper 2011-07-14)
|-
| 6990 || 746 || 1.82|| || 410 || 880 || 3072 || 2.3 || PCI-E 2.1 x16 || mrb's hdminer || BIOS switch at "overclocked" position 1, see [http://www.bitcoin.org/smf/index.php?topic=2949 source]
|-
| 6990 || 758 || -|| || - || 880 || - || 2.4 || - || Phoenix with Poclbm || Catalyst 11.4, OC switch ON, VECTORS AGGRESSION=12 BFI_INT WORKSIZE=128 FASTLOOP=false
|-
| 6990 || 771 || 1.8804|| || 410 || 880 || 3072 || 2.3 || PCI-E 2.1 x16 || mrb's hdminer || SDK 2.1 not supported on 69xx. Memory clock @ 1280Mhz.
|-
| 6990 || 772 || 1.8380|| || 420 || 900 || 3072 || 2.3 || PCI-E 2.1 x16 || Phoenix & Poclbm || OC switch ON + overclocked to 900 mhz, VECTORS AGGRESSION=12 BFI_INT WORKSIZE=128
|-
| 6990 || 790 || -|| || - || 900 || 3072 || 2.3 || PCI-E 2.1 x16 || mrb's hdminer || BIOS switch at "overclocked" position 1; with "aticonfig --odsc=900,1260" to further overclock the GPU to 900 MHz and mem to 1260 MHz, see [http://www.bitcoin.org/smf/index.php?topic=2949 source]
|-
| 6990 || 795 || -|| || - || - || - || 2.4 || || Diablo's miner || BIOS switch at "overclocked" position 1; On Windows Vista, Clocks set at 955,1250. Power control at 20.
Diablo's args: -w 128 -g 5 -v 2 -f 0
|-
| 6990 || 802 || -|| || - || 915 || 3072 || 2.3 || PCI-E 2.1 x16 || mrb's hdminer || BIOS switch at "overclocked" position 1; with "aticonfig --odsc=915,1260" to further overclock the GPU to 915 MHz and mem to 1260 MHz, see [http://www.bitcoin.org/smf/index.php?topic=2949 source]
|-
| 6990 || 835 || -||1.11 || - || 890/860 || 3072 || 2.4 || PCI-E 2.1 x16 || phoenix || BIOS switch at "overclocked" position 1; with "aticonfig --adapter=1 --odsc=990,890 and aticonfig --adapter=0 --odsc=960,860" (GPU 0 runs hot). Currently, aticonfig can only underclock RAM to 100mhz below core speed. Command line: phoenix.py -k poclbm VECTORS AGGRESSION=13 WORKSIZE=128 BFI_INT
|-
| 6990 || 852 || -|| || - || 955|| 3072 || 2.5 || PCI-E 2.1 x16 || cgminer 2.1.2 || Memory: 830 Mhz, -v 2 -w 128 -I 9, Watercooled, stock voltage. (2012-02 by Swapper)
|-
| 6990 || 865 || -||1.11 || - || 890/860 || 3072 || 2.4 || PCI-E 2.1 x16 || cgminer || BIOS switch at "overclocked" position 1; with core 0 at 990/890 engine/mem, core 1 at 960/860 (runs hot). Watercooled at 65-68C.
|-
| 6990x2 || 1436 || 1.848|| || 777 || 880 || 6144 || 2.4 || PCI-E 2.0 x16 x2 || guiminer 2011.05.11 || AUSUM switch set to 1 on both cards; Core left at 880MHz, memory left at 1250MHz; VECTORS AGGRESSION=12 BFI_INT WORKSIZE=128
|-
| 6990x2 || 1640 || 1.416|| || 1200 || 1010 || 3072 || 2.1 || PCI-E 2.0 x16 x16 || phoenix 1.7.0 || GPU 910MHz, Memory 785MHz, Powertune 20%; VECTORS AGGRESSION=12 BFI_INT WORKSIZE=128 FASTLOOP=false
|-
| 6990x2 || 1700 || 1.416|| || 1200 || 1010 || 3072 || 2.1 || PCI-E 2.0 x16 x16 || guiminer 2011.06.14 || GPU 1010MHz, Memory 900MHz; -k phatk2 VECTORS BFI_INT FASTLOOP=false WORKSIZE=128 AGGRESSION=13
|-
| 6990x2 || 1740 || 2.11 || || 825 || 940 || 3072 || 2.1 || PCI-E 2.0 x16 x16 || cgminer 2.0.8 || GPU0+3 930MHz core/805MHz memory, GPU1+2 940MHz core/815MHz memory; BIOS switch factory setting; Cooled with 7C air from outside; -g4 -I9 -k phatk
|-
| 6990x3 || 2094 || -|| || - || 900 || - || 2.4 || PCI-E 2.0 x16 x8 x4 || poclbm || GPU 900MHz, Memory 1250MHz; poclbm.py -f 0 -w 256
|-
| 7750 || 104.15 || || || || 800 || || - || PCI-E 2.0 x16 || phoenix || worksize=128 VECTORS FASTLOOP AGGRESSION=10 WORKSIZE=128
|-
| 7750 || 117.15 || || || || 900 || || - || PCI-E 2.0 x16 || phoenix || worksize=128 VECTORS FASTLOOP AGGRESSION=10 WORKSIZE=128
|-
| 7750 || 125.5 || - || - || - || 830 || 512 || 2.6 (10.0.898.1) || PCI-E 2.0 x8 || DiabloMiner || GPU: 830MHz, Memory: 1125MHz; -v 1 -w 256 [https://bitcointalk.org/index.php?topic=64241.msg816946#msg816946 source]
|-
| 7750 || 134 || 2.66 || 1.21 || 50 || 880 || 512 || 2.6 (?) || PCI-E 2.0 x16 || cgminer 3.1.0 (Gentoo Linux AMD64) || factory-overclocked to 880 MHz; power draw measured with a Kill-a-Watt, intensity=13, vectors=1, worksize=128, kernel=diablo
|-
| 7750 || 136.1 || - || - || - || 900 || 512 || 2.6 (10.0.898.1) || PCI-E 2.0 x8 || DiabloMiner || GPU: 900MHz (CCC locked @ 900), Memory: 800MHz; -v 1 -w 256 [https://bitcointalk.org/index.php?topic=64241.msg816946#msg816946 source]
|-
| 7750 || 140 || - || - || - || 950 || 512 || - || PCI-E 3.0 x16 || bfgminer 3.0.0 || Memory: 900MHz; -I 5 -g 2 -k diablo
|-
| 7770 || 182 || - || - || 83 || 1020 || 640 || 2.6 || PCI-E 2.0 x16 || poclbm || Ubuntu 10.04 LTS amd64, GPU: 1020MHz
|-
| 7770 || 213 || - || - || - || 1150 || 640 || - || PCI-E 2.0 x16 || poclbm || Win7 32bit, Core2Duo, poclbm guiminer
|-
| 7790 || 313 || - || - || - || 1200 || 896|| - || PCI-E 2.0 x16 || poclbm || Saphire Radeon HD 7790 OC (2 fans & heatpipes) GPU 20% OC @ 1200mhz / TEMP 57C / FAN 36%, Win8 64bit, cgminer, "intensity" : "10", "vectors" : "1", "worksize" : "256", "kernel" : "poclbm", "thread-concurrency" : "8192",
|-
| 7790 || 325 || - || - || - || 1300 || 896 || - || PCI-E 2.0 x16 || poclbm || MSI Radeon HD 7790 GPU @ 1300mhz/ MEM @ 750mhz/ FAN @ 83 / TEMP 67C Win7 64bit, athlon x2, poclbm guiminer , -v -w 128 -f 1
|-
| 7850 || 287 || 1,91 || 1,1 || 150 || 950 || 1024 || 2.6 || PCI-E 2.0 x16 || cgminer || GPU:950 MEM:800, Linux 64bit, Intensive 14, GPU temp = 60°C, Room temp = 25°C, Fan = 60%
|-
| 7850 || 329 || - || - || 150 || 1100 || 1024 || 2.6 || PCI-E 2.0 x16 || cgminer 2.6.4 || Linux 64bit GTK+3, GPU temp = 60°C, Room temp = 25°C, Fan = 60%, -v 1 -k poclbm -I 6 --gpu-engine 1100 --gpu-memclock 950
|-
| 7850 || 363 || - || - || - || 1241 || 1024 || 2.6 || PCI-E 2.0 x16 || Guiminer || GPU:1241 MEM:4840
|-
| 7870 || 405 || - || - || - || 1100 || 1280 || 2.6 || PCI-E 2.0 x16 || Guiminer || Sapphire 7870 OC , GPU: 1100MHz, Mem: 950 Mhz, GPU temp: 65°C, Fan 36% (1377 RPM).
|-
| 7870 || 406 || - || - || - || 1100 || 1280 || 2.6 || PCI-E 2.0 x16 || cgminer || Gigabyte GV-R787OC-2GD, GPU: 1200MHz, [cgminer -I 7]
|-
| 7870 || 422 || - || - || - || 1165 || 1280 || 2.6 || PCI-E 2.0 x16 || cgminer || Sapphire 7870 1ghz edition, GPU: 1165MHz, [cgminer.exe -d 0 -l 1 -T -I 8]
|-
| 7870 || 460 || - || - || - || 1250 || 1280 || 2.7? || PCI-E 2.0 x16 || Guiminer || MSI R7870 TFIII/oc, Catalyst 12.11 beta4, 455-460 mhash/s @1250 core, 750 mem, 0% Power limit, 1.218v, Zalman VF3000N = 42C, VRMS = 57C, ambient approx. 17-19C, -v -w128 -f10
|-
| 7870 XT || 485 || 3.09 || 1.8726 || 157 || 1200 || 1280 || 2.8 || PCI-E 3.0 x16 2.0 || cgminer ||7870XT clock/mem - 1200/1600
|-
| 7870xt || 520 || - || - || - || 1200 || 1536 || 2.7? lol || PCI-E 2.0 x4 || Guiminer || Sapphire HD7870xt, Catalyst 12.11 beta 4, 515-520 mhash/s @1200/core 750/mem, 0%PL, 1.17v/stock, Zalman vf3000a @60-62C even though its sandwiched between a 7870 and 5850. xD
|-
|style="background:#00FFFF;"| 7950 || 510 || - || - || - || 985 || 1792 || 2.6 || PCI-E 3.0 x16 || Diablo || Windows 8 x64, Asus P8Z77 WS, i7 3rd Gen, Card is XFX brand, Clock 985Mhz, Mem 1100Mhz, -v 1 -w 256
|-
|style="background:#00FFFF;"| 7950 || 512 || - || - || - || 1000 || 1792 || 2.6 || PCI-E 3.0 x8 || poclbm || GPU: 1000MHz, Memory: 850MHz
|-
|style="background:#00FFFF;"| 7950 || 550 || - || - || - || 1060 || 1792 || 2.8 || PCI-E 3.0 x16 || Diablo || Core 1060, Mem 800, -v 1 -w 256 Intesity 7
|-
|style="background:#00FFFF;"| 7950 || 605 || - || - || - || 1150 || 1792 || 2.6 (10.0.898.1) || PCI-E 3.0 x16 || DiabloMiner || GPU: 1150MHz, Memory: 1375MHz; -v 1 -w 256

|-
|style="background:#FF0000;"| 7970 || 555 || - || - || - || 925 || 2048 || 2.6 (10.0.898.1) || PCI-E 2.0 x16 || DiabloMiner || GPU: 925MHz, Memory: 1375MHz; -v 1 -w 256
|-
|style="background:#FF0000;"| 7970 || 640 || -|| || - || 1070 core/1000 mem || 2048 || 2.6 || PCI-E 3.0 x16 || cgminer 2.6.5 || MSI R7970 Lightning Win7 х64, Catalyst 12.8, GPU 1070 MHz, Memory 1000 MHz, GPU temp = 72°C, Room temp = 28°C, Fan = 57%, cgminer -k diablo -v 1 -w 256
|-
|style="background:#FF0000;"| 7970 || 650 || -|| || - || 1100 || 2048 || 2.4 || PCI-E 2.0 x16 x8 x4 || Diablo|| GPU 1100MHz, Memory 600MHz;
|-
|style="background:#FF0000;"| 7970 || 650 || -|| || - || 1100 || 2048 || 2.6 || PCI-E 2.0 x1 || cgminer 2.4.1 || Win7 х86, Catalyst 12.3, GPU 1100 MHz, Memory 950 MHz, GPU temp = 68°C, Room temp = 25°C, Fan = 58%, -k poclbm -v 1 -w 128
|-
|style="background:#FF0000;"| 7970 || 674 || -|| || - || 1130 core/1000 mem || 2048 || 2.6 || PCI-E 3.0 x16 || cgminer 2.6.5 || MSI R7970 Lightning Win7 х64, Catalyst 12.8, GPU 1130 MHz, Memory 1000 MHz, GPU temp = 72°C, Room temp = 28°C, Fan = 57%, cgminer -k diablo -v 1 -w 256
|-
|style="background:#FF0000;"| 7970 || 685 || -|| || - || 1150 core/1000 mem || 2048 || 2.6 || PCI-E 3.0 x16 || cgminer 2.6.5 || MSI R7970 Lightning Win7 х64, Catalyst 12.8, GPU 1150 MHz, Memory 1000 MHz, GPU temp = 72°C, Room temp = 28°C, Fan = 58%, cgminer -k diablo -v 1 -w 256
|-
|style="background:#FF0000;"| 7970 || 685 || -|| || - || 1177 || 2048 || 2.6 || PCI-E 2.0 x16 || cgminer 2.3.1 || Win7, Catalyst 12.3, driver: 2.95, E: 1177, M:685, -k diakgcn -v 2 -w 256
|-
|style="background:#FF0000;"| 7970 || 690 || - || - || - || 1150 || 2048 || 2.6 (10.0.898.1) || PCI-E 2.0 x16 || DiabloMiner || GPU: 1150MHz, Memory: 1375MHz; -v 1 -w 256
|-
|style="background:#FF0000;"| 7970 || 695 || - || - || - || 1160(core)/1050(mem) || 2048 || 2.6 || PCI-E 2.0 x16 || DiabloMiner (options: -v 1 -w 256) || Asus HD7970-DC2T-3GD5 @ 1.17V; Linux Ubuntu 11.10 64 bit; AMD SDK 2.6; Catalyst 12.3
|-
|style="background:#FF0000;"| 7970 || 710 || -|| || - || 1200 || 2048 || 2.4 || PCI-E 2.0 x16 || DiabloMiner|| GPU 1200MHz, Memory 600MHz; -v 1 -w 256
|-
|style="background:#FF0000;"| 7970 || 714~ || -|| || - || 1210 || 2048 || 2.7 || PCI-E 1.1 x16 || cgminer 2.7.4 || MSI HD7970 R7970-2PMD3GD5/OC, core clock - 1210Mhz, memory clock - 685, core voltage (1.149V - MSI Afterburner, ~1.043V - GPU-Z), memory voltage 1.5V, temperature - 75C at mid-day and 65C w/ AC on at 20C, Catalyst 12.8, Windows 8 Release Preview 32-bit, kernel - poclbm, vector - 1, worksize - 64, intensity - 14, fan - 100%
|-
|style="background:#FF0000;"| 7970 || 825 || -|| || 214 || 1290 || 2048 || 2.4 || PCI-E 2.0 x16 || Bitminter|| Bitminter beta 1.1.1; GPU 1290MHz, Memory
1375MHz (Trixx = 600); work size 256, "BFI_INT," Device-accessible CPU memory; full watercooled block; power stats from GPU-Z; Driver 11.12
|-
| 7970x3 || 1950 || 2.6 || 1.72 || 750 || 1100 || 2048x3 || - || PCI-E 2.0 x16 || cgminer 2.7.5 || Win8, Catalyst 12.8, driver: 8.982.0.0, E: 1100, M:750, kernel: poclbm, worksize: 256, intensity: 9, gpu-threads: 4, refitted Diamond 7970 HSF with new VRM pads to lower VRM temps ~15C. Undervolted each card until crash under load, then raised about 0.015v for stability. Settings using afterburner 2.2.1 with OC unlocked. Visiontek 7970: $370, Sapphire 7970: $360, Diamond 7970: $400
|-
| 7970x3 || 2050 || 2.41 || 1.22 || 850 || 1150 || 6144 || 2.6 || PCI-E 2.0 x16 || cgminer 2.3.1 || Win7, Catalyst 12.3, driver: 2.95, E: 1150, M:685, -k diakgcn -v 2 -w 256, 850W power consumption measured at the wall
|-
| FirePro V3800 || 69.0 || -|| || - || || || || PCI-E 2.0 x16 || BitMinter Client ||
|-
| FirePro V4800 || 79.7 || -|| || - || 775 || 400 || 2.4 || PCI-E 2.1 x16 || GUIMiner v2011-05-01 ||
|-
| FirePro V8700 || 84.8 || -|| || - || 750 || 800 || - || - || poclbm-mod.03.24.2011 ||

|-
| FirePro M5800 || 61.4 || -|| || - || 650 || - || - || - || poclbm-mod.03.24.2011 || Ubuntu
|-
| FirePro M5800 || 69.3 || -|| || - || 650 || 400 || 2.1 || - || GUIMiner v2011-04-26 || -v -w128, Windows 7 32bit
|-
| FirePro M5950 || 96.7 || -|| || - || 725 || 900 || 2.5 || PCI-E 2.0 x16 || poclbm || -v -w128 (Windows 7 64 bit)
|-
| FirePro V5800 || 119 || -|| || - || 690 || 800 || - || PCI-E 2.0 x16 || GUIMiner v2011-05-01 || Windows 7 32bit
|-
| FirePro V5800 || 144 || -|| || - || 690 || 800 || - || PCI-E 2.0 x16 || GUIMiner v2011-05-01 || -v -w128 (Windows 7 32bit)
|-
| FirePro V5800 || 161 || -|| || - || 780 || 800 || - || PCI-E 2.0 x16 || GUIMiner v2011-05-01 || -v -w128 (Windows 7 32bit)
|-
| FirePro V7750 || 35.7 || -|| || - || - || 320 || 2.4 || PCI-E 2.0 x16 || GUIMiner v2011-05-21 || Windows 7 64bit
|-
| FirePro V7800 || 254.85 || -|| || - || - || 1440 || 2.4 || PCI-E 2.0 x16 || Phoenix 1.48 with poclbm || Debian Squeeze
|-
| FirePro M7740 (M97 GL) [DELL] || 63.0 || -|| || - || 650 || - || 2.1 || PCIe v2.0 x16 || GUIMiner v2011-06-14 || Windows 7 64bit / only SDK2.1 works
|-
| FirePro M7820 || 150.0 || -|| || - || 700 || 800 || 2.1 || PCI-E 2.1 x16 || GUIMiner v2011-06-09 / poclbm || Memory downclocked to 500 from 1000MHz, 169MH/s@800MHz, 181MH/s@860Mhz (max.), only SDK2.1 works, Windows 7 x86
|}

<references>
<ref name='amazon_20110625'>$ Prices from http://www.amazon.com on 2011-06-25</ref>
</references>

===Nvidia===

{| class="wikitable sortable"
|-
! Model !! Mhash/s !! Mhash/J !! Watts !! Clock !! SP !! Comment
|-
| ION || 1.8 || 0.067 || 27 || || 16 || poclbm; power consumption incl. CPU
|-
| 8200 mGPU || 1.2 || || || 1200 || 16 || 128 MB shared memory, "poclbm -w 128 -f 0"
|-
| 8400 GS || 2.3 || || || || || "poclbm -w 128"
|-
| 8400 GS || 1.6 || 0.013 || 128 || 1238 || || DiabloMiner -w 128 -f 1 [https://en.bitcoin.it/wiki/User:Knightmb source]
|-
| 8400M GS || 2.0 || || || || ||
|-
| 8500GT || 2.4 || || || 918 || 16 || poclbm under GUIMiner
|-
| 8600M GT || 4.93 || || || || 32 ||
|-
| 8600M GT || 3.8 || || || || || Macbook Pro running Diablo
|-
| 8600GT || 5.66 || || || 1188 || 32 ||
|-
| 8600GT OC || 7.3 || || || 1602 || 32 || [http://www.bitcoin.org/smf/index.php?topic=1334.0 poclbm] -w 128 [http://www.bitcoin.org/smf/index.php?topic=4967.msg72833#msg72833 source]
|-
| 8800GT || 25 || 0.24 || 105 || 1300 || ||
|-
| 8800GT || 24.5 || 0.23 || 105 || 1300 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]
|-
| 8800GT || 31.1 || 0.296 || 105 || 1855 || || Overclocked 715 GPU / 1030 Memory / 1855 Shader; GuiMiner v2011-05-21
|-
| 8800GT || 31.8 || 0.303 || 105 || 1836 || 112 || 713 gpu, 1026 memory. win7x86, phoenix 1.48, -k poclbm WORKSIZE=64 AGGRESSION=5
|-
| 8800GT || 34.0 || || 105 || 1998 || || gpu 756M, mem 1123M, shader 1998M, temp 65C. winXP, phoenix 1.50, -k poclbm WORKSIZE=64 AGGRESSION=6 -- same settings get 32.7 MH/s with aggression 2
|-
| 8800GTS || 16.8 || 0.109 || 154 || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]
|-
| 8800 GTS || 18.7 || 0.124 || 150 || 1200 || || poclbm -w 64 no vectors
|-
| 8800 GTS || 33.5 || || 150 || OC || || CUDA mining via GUIminer. Win7 64bit. poclbm -v -w128 -f0. OC'd Core@799MHz, Mem@1080MHz, Shader@1905MHz. Fan 70%, GPU temp @ 66C in comfortable room temp.
|-
| 8800 GTX || 27.5 || || || 1404 || || phoenix 1.48, poclbm, no vectors, 83C with 50C ambient
|-
| 8800m GTX || 16.3 || || || || || rpcminer-cuda Win7-64
|-
| 9300GE || 1.57 || || || 1300 || 8 ||
|-
| 9300GS || 1.69 || || || 1400 || 8 ||
|-
| 9300/nForce 730i || 2.15 || || || 1200 || 16 ||
|-
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||
|-
| 9400M (MacBook) || 1.90 || 0.32 || 6 || 700 || || poclbm -f 8 no vectors
|-
| 9500M GS || 3.2 || || || 950 || 32 || rpcminer-cuda
|-
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||
|-
| 9500GT || 7.30 || 0.135 || 50 || 1400 || 32|| rpcminer-cuda, Overclocked 730 GPU/ 500 Memory / fan 100% 70C solid
|-
| 9500GT || 7.10 || 0.135 || 50 || 1767 || 32 || rpcminer-cuda, Overclocked 707 GPU / 500 Memory / fan 100% 73C steady
|-
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||
|-
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||
|-
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||
|-
| 9600GT Zotac || 15 || || || 1650 || 64 ||
|-
| 9600GT OC || 18.8 || <0.198 || >95 || 1981 || 64 || [http://www.bitcoin.org/smf/index.php?topic=1334.0 poclbm] -w 128 -f 10 [http://www.bitcoin.org/smf/index.php?topic=4967.msg74610#msg74610 source] [http://www.bitcoin.org/smf/index.php?topic=4967.msg73353#msg73353 source]
|-
| 9600M GS || 4.0 || || || 1075 || 32 || rpcminer-cuda
|-
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||
|-
| 9800GT EE || 19.7 || 0.263 || 75 || 1375 || 112 || rpcminer-cuda
|-
| 9800GT OC || 29.5 || 0.283 || 105 || 1836 || 112 || poclbm.py, no options. Memory underclocked to 850Mhz, GPU overclocked to 733Mhz
|-
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||
|-
| 9800GTX+ || 32.6 || 0.232 || 140 || 1688 || 128 || win7x64 275.33 Overclocked to 756/1890/1102 using a CUDA-specific miner (instead of phoenix, yay for ZERO stales!)
|-
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||
|-
| 9800GTX+ || 36 || || || || || factory OC ubuntu polclbm.py -w 128 -f 10 -a 10 (DO NOT USE -v)
|-
| 9800GTX+ || 37.23 || 0.266 || 140 || 1890 || 128 || win7x64 275.27 phoenix(1.48) -k poclbm AGGRESSION=3 WORKSIZE=64 (may cause 75%+ stale count, in which case use a CUDA-specific miner instead)
|-
| 9800GTX+ || 40.20 || 0.287 || 140 || 835 || 128 || lowered memory clock higher core, unstable if going higher
|-
|style="background-color:#FFEFEF"| 9800GX2 || 57.83 || 0.294 || 197 || || 2x128 ||
|-
|style="background-color:#FFEFEF"| 9800GX2 || 28 || 0.142 || 197 || || 2x128 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37620#msg37620 source]
|-
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||
|-
| G210 || 3.79 || 0.124 || 30.5 || 1402 || 16 || poclbm -f 1
|-
| GT220 || 10.8 || 0.084 || 128 || 1360 || || DiabloMiner -w 128 -f 1000 [https://en.bitcoin.it/wiki/User:Knightmb source]
|-
| GT230 || 15.5 || 0.161 || 96 || 650 || 64 || (9600GT rebranded one from in a medion pc)
|-
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||
|-
| GT240 || 21.24 || || || || 96 || [http://www.bitcoin.org/smf/index.php?topic=4291.0 poclbm-mod] -f 0 -v [http://www.bitcoin.org/smf/index.php?topic=4967.msg73383#msg73383 source]
|-
| GT240 || 28.1 || || || || 96 || poclbm -f0 -v (Gainward GT240 1024DDR5 OC core@670/stockmem@1700/shader@1700 - stable; max.temp=73)
|-
| GT240M || 9.8 || 0.426 || 23 || 550 || 48 || poclbm -f 0 -w 256
|-
| GT240 OC || 25.6 || 0.365 || 70 || 1765 || 96 || poclbm
|-
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||
|-
| GTS250 || 35.2 || 0.243 || 145 || 1836 || 128 ||
|-
| GTS250 OC || 37 || 0.255 || 145 || 2047 || 128 || 37.2 with the following OC: Core: 775MHz, Shader: 1900MHz, Memory: 1200MHz
|-
| GTX260M || 22.5 || || || 500 || 112 || poclbm 4/28/2011 Asus G71GX runs ~90c without cooling pad
|-
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||
|-
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]
|-
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||
|-
| GTX260c216 || 47.4 || 0.260 || 182 || 1348 || 216 || poclbm -w 256
|-
| GTX260c216 || 50.00 || || || 1050 || 216 || m0mchil GPU client, Windows 7 64-bit, x6 @ 3.5ghz
|-
| GTX260c216 OC || 52.0 || || || 1461 || 216 || "poclbm -w 256 -f 1"
|-
| GTX260c216 OC || 58.9 || || || 756/400 || 216 || Core overclocked, Memory underclocked, Ubuntu 11.04 Classic Session(No Effects) "poclbm -w 256 -f 1"
|-
| GTX260c216 OC || 60.1 || || || 1706 || 216 || Core: 364 MHz, Shaders: 1706 MHz, Memory: 594 MHz, VDDC: 1.1800V. "poclbm-mod -w 256 -f 1"
|-
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||
|-
| GTX275 || 58 || || || 729/1458 || 240 || poclbm -f 0 -w 256
|-
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||
|-
| GTX280 || 64.34 || 0.289 || 245 || 1296 || 240 || phoenix.exe -k poclbm AGGRESSION=6 WORKSIZE=128 (61*C with Accelero XTREME GTX280)
|-
| GTX285 || 64.8 || || || 1607 || 240 || GuiMiner - Not sure about wattage yet. Still testing. Card runs around 74 C
|-
|-
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||
|-
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||
|-
| GTX295 || 120.70 || 0.418 || 289 || 1242 || 480 || GUIMiner no oc.
|-
| GTX295 || 117.30 || 0.406 || 289 || 1476 || 490 ||
|-
| GT 320M (MacBook Air) || 6.12 || || || 1212 || 48 ||
|-
| 320M (Mac mini 2010) || 7.0 || 0.35 || 20 || 450 || 32 || poclbm no extra options, windows 7 x64
|-
| GT 325M || 7.5 || || || 990 || 48 || rpcminer-cuda
|-
| GT 325M || 10.5 || || || 325/650(mem)/1300(shaders) || || rpcminer-cuda, 71 degrees
|-
| GT 325M || 7.99 || || || || || poclbm -f 0 -w 256
|-
| GT330 || 21.65 || || || || || poclbm -f 0 -w 256
|-
| GT 330M || 7.97 || || || ||48|| Model: MacBookPro6,2 VRAM: 512MB Software: [http://forum.bitcoin.org/index.php?topic=8994.0 DiabloMiner GUI] v2011-05-22 / Mac OS X 10.6.7
|-
| GT 330M || 10.8 || || ||650MHZ core||48|| Model: MacBookPro6,2 VRAM: 512MB Software: GUIMiner running in Bootcamp v2011-08-24 / Mac OS X 10.6.8.The GPU was OC'd to 650MHZ core clock,mem clock was the lowest it would go in MSI Afterburner.The Bootcamp OS was Windows 7 x64.MBP Mid 2010.
|-
| GT 330M (Sony Vaio Z) || 7.8 || 0.71 ( 0.3 total) || 11 (26w total) || 1045 || 48 ||
|-
| GT 330M (Samsung R480) || 9.1 || || || 575(GPU)/1265(shader) || ||VRAM 1024MB. pocblm -vectors --verbose. Windows 7 Ultimate x86
|-
| GTS 350M (Toshiba A665-3DV) || 17.0 || 1.214 || 14 || 1080 || || DiabloMiner-Windows.exe
|-
| GTS 350M (Toshiba A665-3DV5) || 20.8 || || || 1350 || || DiabloMiner-Windows.exe, OC'd 550/850/1350 73C stable
|-
| GTS 360M || 25.0 || || || || || [toshiba qosmio laptop, ~150-165*F stock fans]
|-
| GTS 360M (ASUS G60jx) || 20.0 || || || || || everythins is stock, it cannot sustain. it reaches 90 degrees and freezes.
|-
| GTS 360M (ASUS G60jx) || 27.2 || || || Shader @ 1720, Memory @ 900 || || stock hardware (clean exhaust fan), Afterburner, 72 deg C Stable
|-
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||
|-
| GT440 || 20.4 || || || 1645 || 96 || rpcminer-cuda -aggression=8; winxp x64 driver 275.33
|-
| GT530 || 17.9 || 0.358 || 50 || 1400 || || BitMinter v1.1.2
|-
| GT520M || 8.9 || || || || || rpcminer-cuda, got up 2 10.2MH/s OC'ed
|-
| GT525M || 14.6 || || || || || rpcminer-cuda
|-
| GT540M || 16.0 || || || || || rpcminer-cuda
|-
| GT550M || 17.08 || || || || || rpcminer-cuda -aggression=8
|-
| GT610M (ASUS K45V) || 9.371 || || || 738 MHz || || 2GB RAM.
|-
| GT650M (rMBP) || 17.8 || || || 900 || 16 || cgminer 2.5.0 on OSX 10.7.4
|-
| GT650M OC || 27.4 || || || || || GUIMiner
|-
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||
|-
| GTS450 (Sparkle One) || 40.0 || || || || || poclbcm git Oct 2012
|-
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||
|-
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||
|-
| GTX460 || 66.32 || || || 814 || 336 || rpcminer-cuda 20110605, Graphics Clock @ 814MHz, Memory @ 1555MHz
|-
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||
|-
| GTX460 768MB || 57.8 || || ? || 1350 || 336 || rpcminer-cuda -gputhreads=320 -gpugrid=336
|-
| GTX460 768MB (MSI Cyclone 768D5/OC) || 75.1 || || ? || 930 || 336 || rpcminer-cuda on Win7 x64 with ForceWare 275.33. [http://event.msi.com/vga/afterburner/download.htm MSI Afterburner] set to core: 930MHz, shader: 1850MHz, core voltage: 1.087V, memory: 1600MHz. Runs at 58°C with fan at 75% (ambient 25°C).
|-
| GTX460 1GB DirectCU || 72.3 || ? || ? || 1672 || 336 || rpcminer-cuda -gputhreads=320 -gpugrid=336
|-
| GTX460 1GB DirectCU || 89.5 || ? || ? || 1000 || 336 || guiminer GPU:1000mhz MEM:900
|-
| GTX460 1GB ( evga FPB ) || 71.4 || -- || -- || 870/1744/1800 || 336 || guiminer-cuda v2012-02-19 FW290.53 Win7x64
|-
| GTX460 1GB ( evga ) || 83.1 || 0.519 || 160 || 925/1850/900@0.960v || 336 || guiminer (phoenix1.75) -k poclbm AGGRESSION=8 FASTLOOP BFI_INT -v WORKSIZE=256 ForceWare 301.42 Win7x64 Runs at 70°C with fan at 100%
|-
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]
|-
| GTX460 (2 cards) OC || 127 || 0.374 || 340 || 1620 || 2x 336 || [http://www.bitcoin.org/smf/index.php?topic=2444.0 rpcminer-cuda] -gpugrid=128 -gputhreads=128 ver.20110227
|-
| GTX460 1GB OC (2x MsiHawksSLI) || 158 || 0.658 || 240w(used kill a watt) || core/shader/ram@vcore 930/1860/1150@1.087v (only vcore raised) || 2x 336 || rpcminer-cuda ver.20110227 -gpugrid=320 -gputhreads=320 -aggression=7 Watercooled stable @ 110°F/43° !!!USE ASUS GPU Tweak with GPU-Z (afterburner v2.2.3 wont OC with NVIDIA driver 306.97) I would need gpu bios mod to get more oc/volt. Setting faster ram did increase Mhash/s versus setting ram=core clock.
|-
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||
|-
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||
|-
| GTX470 || 94.7 || || || 1414 || ||
|-
| GTX470 || 103.7 || || || 1520 || || memory @ 418MHz, stable @ 72 deg fan @ 90%, puddinpop rpcminer-cuda -gpugrid=96 -gputhread=128 AGGRESSION=14 GIGABYTE brand card BIOS 70.00.21.00.03
|-
| GTX470 || 111.9 || 0.520 || 215 || 1650 || 448 ||
|-
| GTX470 || 115 || || || 1616 || || phoenix 1.46 poclbm VECTORS BFI_INT FASTLOOP AGGRESSION=6
|-
| GTX470x2 || 121 ea. (130 burst ea.) || || || 1700 ||448|| PuddinPop rpcminer-cuda -gpugrid=96 -gputhreads=128 AGGRESSION=14 (memory 856 Max Temp. 71 deg. F on Water 1.085v+, Stable on Beast 2.0>3 days, no i7 CPU OC, driver 280.26, bios 70.00.21.00.03)
|-
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||
|-
| GTX480 || 140.43 || || || 1700 || 480 || rpcminer-cuda -gpugrid=512 -gputhreads=480
|-
| GTX480 AMP!Zotac|| 140.1 || || || 1700|| 480 || rpcminer-cuda -gpugrid=480 -gputhreads=480 (vCore-1050,Core Clock-851, Shader Clock-1702, Memory Clock-2033, t-79°c, Water 43°c, stable temperature and work)
|-
| GTX550 Ti || 45.0 || ? || ? || ? || ? || EVGA 1GB, WinXP rpcminer, no overclock
|-
| GTX560 Ti || 67.7 || 0.39 || 170 || 1700 || 384 || standard EVGA 560, no overclock
|-
| GTX560 Ti || 74 || 0.41 || 170 || 822 || 384 || MSI 560Ti HAWK; core 822 Mhz clock (no overclock); rpcminer-cuda.exe -aggression=4 -gpugrid=64 -gputhreads=384; temp - 71°C; Win 7 x64
|-
| GTX560 Ti || 74.8 || 0.41 || 180 || 1700 || 384 || gigabyte 900Mhz clock; -w 512 -v
|-
| GTX560 Ti || 81 || 0.45 || 180 || 835 || 384 || Gainward GTX560TI Phantom, default clock, rpcminer-cuda
|-
| GTX560 Ti || 85.1 || - || - || - || - || cgminer 2.5.0, linux 32bit, nvidia 295.41, Intensity: 14
|-
| GTX560 Ti || 100 || 0.5 || 200 || 1000 || 384 || GFX - MSI 560Ti HAWK; rpcminer-cuda.exe -aggression=8 -gpugrid=64 -gputhreads=384; GPU temp - 68°C; OS - Windows 8 x64 .
|-
| GTX 560M || 39.3 || 0.38 || 75 W || 775|| 192 || [http://www.examiner.com/computers-in-denver/toshiba-qosmio-x775-q7380-review-review source1] [http://www.notebookcheck.net/NVIDIA-GeForce-GTX-560M.48313.0.html source2] Note: Uses the 295.51 Beta Drivers
|-
| GTX560 OC || 86.7 || <0.51 || >170 || 1800 || 384 || [http://www.bitcoin.org/smf/index.php?topic=2444.0 rpcminer-cuda] [http://www.bitcoin.org/smf/index.php?topic=4967.msg72816#msg72816 source]
|-
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||
|-
| GTX570 || 140 || 0.639 || 219 || 750 || 480 || rpcminer-cuda.exe -aggression=10 -gpugrid=480 -gputhreads=960; display driver stops working with aggression=11 under win7 x64 driver 270.61
|-
| GTX570 || 157 || 0.717 || 219 || 850 || 480 || rpcminer-cuda.exe -aggression=11 -gpugrid=120 -gputhreads=960
|-
| GTX570 || 165 || || || 925 || 480 || rpcminer-cuda.exe -gpugrid=120 -gputhreads=960; vcore 1.1v; Win7 x64 304.79 Beta; -aggression=11 adds strong lag with minimal increase in hashrate.
|-
| GTX570 || 160 || || || 925 || 480 || rpcminer-cuda.exe -gpugrid=104 -gputhreads=832; No desktop lag, very minimal loss in hashrate compared to much laggier settings
|-
| GTX580 || 156.6 || 0.642 || 244 || 1544 || 512 || cgminer 2.11.3 on Win 8-64 with I=6, driver nVidia 314.22
|-
| GTX580x2 || 2x 146 || 0.598 || 244 || 1544 || 512 || rpcminer-cuda.exe -gpugrid=128 -gputhreads=1024
(aggression levels above the default of 6 not recommended; only a gain of ~3MH/s per card, and '''heavy''' lag, GUIMiner v2011-08-24, win7 64bit nVidia 290.36 beta driver)
|-
| GTX590 || 193.1 || --- || --- || 1215 || 2x 512 || poclbm -v -w 256, Win
|-
| GTX590 || 2x 121.48 || --- || --- || 750 || 2x 512 ||
|-
| GTX670 || 112.00 || 1.1 || 100 || 1275 || 1344 || EVGA GTX670FTW 2GB / GPU Clock offset +75Mhz with EVGA Precision X / GUIMiner -f 60 / Windows 7 64-Bit. (09-13-2012)
|-
| GTX680 || 127.3 || || || 1280 || 1536 || Asus GTX 680 2GB DirectCU II: Windows 7 64 bit: Nvidia 310.90 driver: Offset of 186: Runs at a constant 52C
|-
| GTX680 || 110.00 || || || 1110 || 1536 || RPCMiner with OpenCL or others. Might crash once mining stops. No Flags and Stock Settings (GPU Boost @ 1110mhz Core) with EVGA GTX 680, latest version of GUIMiner (2012-2-19) and Windows 7 x64.
|-
| GTX680 || 120.00 || 1.2 || 100 || 1272 || 1536 || Ufasoft Galaxy 4GB (GPU Clock offset +70Mhz with EVGA Precision X) (2012-7-28) and Windows 7 64-Bit.
|-
| Quadro FX 580 || 5.7 || 0.14 || 40 || 1125 || 4 ||rpcminer-cuda, Win, -gpugrid=128 -gputhreads=512
|-
| Quadro FX 770M || 5.75 || || || 500 || 32 || DiabloMiner-Windows.exe BFI_INT FASTLOOP AGGRESSION=6, Win
|-
|Quadro FX 770M || 6.39 || || || 500 || 32 || DiabloMiner-Windows.exe BFI_INT FASTLOOP AGGRESSION=6 w 64, Win 7x64
|-
|Quadro FX 880M || 9.6 || || || || || poclbm/guiminer
|-
| Quadro FX 1600M || 6 || 0.12 || 50 || 625 || 32 ||rpcminer-cuda, Win
|-
| Quadro FX 1800 || 13.6 || - || - || - || - || cgminer 2.5.0, linux 32bit, nvidia 256.44 Intensity: 4
|-
| Quadro FX 2000M || 23 || 0.397 || 58 || || || phoenix 1.48, -k poclbm, VECTORS, AGGRESION=6, Lenovo W520 platform
|-
| Quadro FX 2800M || 22 || 0.293 || 75 || 600 || 96 ||DiabloMiner, win
|-
| Quadro FX 3000M || 28.6 || - || - || - || - || cgminer 2.5.0, linux 32bit, nvidia 295.41 Intensity: 3
|-
| Quadro FX 3600M || 36 || 0.514 || 70 || 500 || 96 ||
|-
| Quadro FX 3800 || 33.3 || || || || || poclbm/guiminer -f0 -w128
|-
| Quadro NVS 135M || 1.05 || 0.1 || 10 || 800 || 1 ||
|-
| Quadro NVS 295 || 1.7 || 0.07 || 23 || 567 || 8 || phoenix
|-
| Quadro NVS 3100M || 3.6 || 0.257 || 14 || 600 || 16 || rpcminer-cuda, Win, CUDA 3.1.1
|-
| Quadro NVS 4200M || 10.0 || || || 810 || || guiminer, Win7-64
|-
| Quadro 5000 || 67.7 || 0.445 || 152 || 513 || 352 || rpcminer-cuda.exe -aggression=7 gpugrid=352 gputhreads=704;
|-
| Tesla C1060 || 52.5 || || || 1296 || 240 || poclbm, Win7x64
|-
| Tesla K20 || 134.8 || || || 706 || 2496 || poclbm, Linux
|-
| Tesla M2050 || 79.8 || || || 1550 || 448 || DiabloMiner
|-
| Tesla M2050 || 94.5 || || || 1550 || || poclbm
|-
| Tesla S1070 || 155.2 || || 800 <ref name='nvidia_S1070'/> || 1440 (GT200b)<ref name='nvidia_S1070'/> || 960<ref name='nvidia_S1070'/> || rpcminer-cuda, Linux, CUDA 3.2, 4 instances (-gpu=0 through -gpu=3)
|-
| Tesla S2070 || 749.23 || || || 1150<ref name='nvidia_S2070'/> || 1792<ref name='nvidia_S2070'/> || rpcminer-cuda, Linux, CUDA 4.0, 8 instances (-gpu=0 through -gpu=7)
|-
| GTX280x2 || 102.7 || || || || ||
|-
|}
<references>
<ref name='nvidia_S1070'>The S1070 is a dedicated supercomputing platform that features four Tesla units (GT200). Technical data taken from [http://www.nvidia.de/object/tesla_s1070_de.html NVIDIA]</ref>
<ref name='nvidia_S2070'>The S2070 is a dedicated supercomputing platform that features four Fermi units (C2070). Technical data taken from [http://de.wikipedia.org/wiki/Nvidia_Tesla Wikipedia] (Documentation from NVIDIA webpage is confusing)</ref>
</references>

==CPUs/APUs==

A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section.

Might you wish to throttle CPU load a bit, so it doesn't reach 100°C, it can be done with Battle Encoder Shirase to a margin, like, -15% of available CPU cycles.

Often, the best combination to be is to throttle CPU miner to -5% '''AND''' set it to least of priority levels, so as not to choke GPU miner up.

===AMD===
{| class="wikitable sortable"
|-
! Model !! nprocs !! Mhash/s !! Mhash/J !! TDP [W] !! CPU Clock !! Mhash/s CPU !! Mhash/s GPU !! GPU !! GPU Clock !! SP !! Software !! Notes
|-
| 4x Opteron 6174 || 48 || 115 || 0.36 || 320W || 2.2 GHz || 2.4
|colspan=4|
| cpuminer v0.8.1 || --alg 4way --threads 48
|-
| 2x Opteron 6172 || 24 || 55 || 0.24 || 230W || 2.1 GHz || 2.3
|colspan=4|
| cgminer v2.7.6 || --algo 4way -t 24
|-
| 2x Opteron 6128 || 16 || 32.4 || 0.141 || 230W || 2 GHz || 32.4
|colspan=4|
| 0.3.19 || -4way
|-
| Athlon XP 2000+ || 2 || 0.62 || 0.009 || 70W || 1.67 GHz || 0.62
|colspan=4|
| 0.3.18/Ubuntu || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source] [http://www.pcstats.com/articleview.cfm?articleid=914&page=4 source]
|-
| Athlon 64 3500+ || 1 || 1.18 || 0.013 || 89W || 2.54 GHz || 1.18
|colspan=4|
| ufasoft v0.4 || overclocked (originally 2.2 GHz)
|-
| Athlon 64 X2 3800+ || 2 || 1.73 || 0.03 || 65 W || 2.00 GHz || 1.73
|colspan=4|
| cpuminer (v0.8.1-1-g69529c3) || -algo=4way
|-
| Athlon 64 X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || 1.9
|colspan=4|
| rpc-miner ||
|-
| Athlon 64 X2 4400+ || || 2.09 || 0.032 || 65W || 2.3GHz || 2.09
|colspan=4|
| 0.3.19/Win x64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]
|-
| Athlon 64 X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || 2.81
|colspan=4|
| || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]
|-
| Athlon 64 X2 6400+ Black Edition || 2 || 2.9 || 0.023 || 125W || 3.2 GHz || 2.9
|colspan=4|
| 0.3.20.2 BETA/Win 7 x64 || -4way
|-
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || 2.71
|colspan=4|
| bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]
|-
| Athlon II X2 250 || 2 || 5.6 || 0.09 || 65W || 3.01GHz || 5.6
|colspan=4|
| bitcoin-miner 0.11 ||
|-
| Athlon II X4 630 || 4 || 10.7 || 0.11 || 95W || 2.8 GHz || 10.7
|colspan=4|
| bitcoin-miner 0.4 ||
|-
| Opteron 8220 x16 || 16 || 25 || || || 2.8Ghz || 1.5
|colspan=4|
| ufasoft / OpenSuse 64bit || running default, but had to copy 32bit binaries over to get curl and ufasoft running. might be better when using native 32bit system w/o other users on the machine ||
|-
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 3.8
|colspan=4|
| 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]
|-
| Phenom X4 9950 BE || 4 || 9.3 || 0.07 || 126W || 2.6 GHz || 2.32
|colspan=4|
| bitcoin-miner 0.13/WinXP || No GPU
|-
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || 7.2
|colspan=4|
| cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]
|-
| Phenom II X4 810 || 4 || 5.0 || || 95W || 2.8 GHz ||
|colspan=4|
| rpcminer-cpu ||
|-
| Phenom II X4 810 || 4 || 9.5 || || 95W || 2.8 GHz ||
|colspan=4|
| rpcminer-4way ||
|-
| Phenom II X4 810 || 4 || 10.5 || || 95W || 2.8 GHz ||
|colspan=4|
| ufasoft v0.10 ||
|-
| Phenom II X4 810 || 4 || 11.5 || || 95W || 2.8 GHz ||
|colspan=4|
| cgminer 1.5.3 || "cgminer 1.5.3 --algo 4way" on Ubuntu 11.10 alpha 2 (64 bit), built by GCC 4.6.1 with "-O3 -Wall -march=native"
|-
| Phenom II X4 955 || 4 || 11 || 0.09 || 125W || 3.2 GHz || 11
|colspan=4|
| rpcminer-4way ||
|-
| Phenom II X4 965 || 4 || 12 || 0.09 || 140W || 3.4 GHz || 11
|colspan=4|
| rpcminer-4way ||
|-
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || 15.84
|colspan=4|
| bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]
|-
| Phenom II X6 1055T || 6 || 23.6 || || 95W || 3.50 GHz || 23.6
|colspan=4|
| [http://github.com/pooler/cpuminer pooler's cpuminer] 2.2.2 || --algo=sha256d
|-
| Phenom II X6 1075T || 6 || 21.3 || || 125W|| ||
|colspan=4|
| minerd || Ubuntu 11.04 amd64 runlevel=1 -algo=4way -threads=6
|-
| Phenom II X6 1090T || 6 || 18|| || 141W|| 3.50 GHz || 3
|colspan=4|
| minerd ||
|-
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || 22
|colspan=4|
| bitcoin-miner || Aciid#bitcoin-dev
|-
| Sempron 3000+ || 2 || 0.8 || || 62W || 1.6 GHz || 0.8
|colspan=4|
| cpuminer || --alg 4way
|-
| Turion X2 RM-70 || 2 || 1.9 || || 65W || 2.1 GHz || 1.9
|colspan=4|
| cpuminer || --alg 4way
|-
| Zacate E-350 || 2 || 11 || 0.615 || 18W || 1.6 Ghz || 1.231 || 9.831 || HD6310M || 492 Mhz || 80 || poclbm -v -w128 + Ufasoft 0.7 || stock speeds
|-
| Zacate E-350 || 2 || 12
|colspan=2|
| 1.648 Ghz || 1.252 || 10.87 || HD6310M || 492 Mhz || 80 || poclbm -v -w 256 -f 1 || "autotune" speed with ASUS EFI BIOS
|-
| Ontario C-50 || 2 || 6.2 || 0.68 || 9W || 1.0 Ghz || 1.200 || 6.2 || HD6250M || 277 Mhz || 80 || poclbm -v -w128 -f5 -r5 ||
|-
| A4-3400 || 2 || 23.2 || || || 75W || 2.4 Ghz || || 23.2 || 6350 || stock || || GUIminer || ||
|-
| A8-3850 || 4 || 60 || || 100W || Stock || || 60 || HD6550D || Stock || 400 || poclbm.exe, Win7-32, 4GB RAM || All running at stock speeds, and set to auto in BIOS.
|
|-
| A8-3870K || 4 || 95 || || 100W (@stock) || 3.3 Ghz || || 95 || HD6550D || 900MHz || 400 || phoenix.exe -k phatk VECTORS BFI_INT AGGRESSION=4 WORKSIZE=128, Win7-64, 8GB RAM 1667MHz || M/B ASUS F1 A75-M Pro, CPU/GPU BIOS overclocked
|-
| A10-5800K || 4 || 105 || || 100W || 3.8 Ghz || || 105 || HD7660D || 800MHz || 384 || cgminer Intensity=7 || Linux 64bit (Ubuntu 12.10), AMD-APP-SDK-v2.7-RC-lnx64, stock speeds *not* overclocked
|}

===ARM===
{| class="wikitable sortable"
|-
! Model !! p/t !! Mhash/s !! Mhash/J !! Mhash/s/$ /€ !! ACP [W] !! Clock !! Version !! Comment
|-
| ARM926EJ-S || 1 || 0.187 || ? || ? || ? || 1.2 GHz || cpuminer || Seagate Dockstar [http://archlinuxarm.org/platforms/armv5/seagate-dockstar ArchLinux]
|-
| Marvel Feroceon (88FR131) || 1 || 0.195 || 0.224 ||<0.01|| 0.87 W || 1.2 GHz || cpuminer git (2011-06-15) || Marvell SheevaPlug, Debian, 'c' algo
|-
| ARM1136EJ-S || 1 || 0.11 || ? || ? || ? || 0.528 GHz || cpuminer git || T-Mobile Pulse, inside Debian chroot, 'c' algo
|-
| ARM1176JZ(F)-S || 1 || 0.119 || ? || ? || ? || 0.412 GHz || [http://github.com/pooler/cpuminer pooler's cpuminer] 2.2 || iPhone 3G, 'sha256d' algo
|-
| ARM1176JZ(F)-S || 1 || 0.2 || ? || ? || 3.75W || 800 Mhz || cgminer 2.5.0 || RaspberryPi Model B, SoC BCM2835, Debian Squezee 19-04-2012, Overclocked Cpu 800mhz
|-
| Cortex-A8 || 1 || 0.125 || 0.36 || <0.01 || 0.35 W || 0.6 GHz || cpuminer git (2011-03-26) || Nokia N900: 'cryptopp'
|-
| Cortex-A8 || 1 || 0.2 || 0.57 || <0.01 || 0.35 W || 0.6 GHz || cpuminer git (2011-03-26) || Nokia N900: 'c' algo
|-
| Cortex-A8 || 1 || 0.365 || ? || ? || ? || 0.6 GHz || [http://github.com/pooler/cpuminer pooler's cpuminer] || BeagleBoard: 'sha256d' algo
|-
| Cortex-A8 || 1 || 0.435 || ? || ? || ? || 0.8 GHz || [http://github.com/pooler/cpuminer pooler's cpuminer] 2.2 || 'sha256d' algo
|-
| Cortex-A8 || 1 || 0.44 || ? || ? || ? || 0.8 GHz || cpuminer 2.2.3 (-mfpu=neon) || EfikaMX (iMX.51), CRUX ARMHF, cpuminer -a sha256d
|-
| AllWinner A10(A8) || 1 || 0.568 || ? || ? || <2.5W || 1.0 GHz || [http://github.com/pooler/cpuminer pooler's cpuminer] 2.2 || -a sha256d #Native Lubuntu armhf build
|-
| Cortex-A9 || 2 || 0.57|| 1.14 ||<0.01 || 0.5 W || 1.0 GHz || cpuminer git (2011-03-24) || Toshiba AC100, ubuntu, 'c' algo
|-
| Cortex-A9 || 2 || 1.3 || ? || ? || ? || 1.2 GHz || [http://github.com/pooler/cpuminer pooler's cpuminer] 2.2.3 || Samsung Galaxy S II - CFLAGS="-O3 -mfpu=neon"
|}

===Intel===
{| class="wikitable sortable"
|-
! Model !! p/t !! Mhash/s !! Mhash/J !! Mhash / $<ref name='amazon_20110625'/>/€<ref name='geizhals_20110625'/> !! ACP [W] !! Clock [GHz] !! Version !! Comment
|-
| Pentium III (Coppermine) || 2 || 0.39 || 0.008 |||| TDP 2× 26.1 W || 1 || Ufasoft 0.32 (compiled from source), Debian Squeeze || [http://en.wikipedia.org/wiki/List_of_Intel_Pentium_III_microprocessors#.22Coppermine.22_.28180_nm.29 source]
|-
| Pentium III mobile ? || 1 || 0.3 || 0.014 |||| 21 || 1.07 || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]
|-
| Pentium M 1.6ghz || 1 || 0.4 || || || || 1.6 || minerd (jgarzik's 1.0) || cryppto, Windows 7
|-
| Pentium M 1.6ghz || 1 || 0.62 || || || || 1.6 || Ufasoft 0.20 || Windows XP Professional
|-
| Pentium M 1.6ghz || 1 || 0.71 || || || || 1.6 || [http://github.com/pooler/cpuminer pooler's cpuminer] 2.2 || Gentoo Linux
|-
| Pentium M 1.73ghz || 1 || 0.5 || || || || 1.73 || minerd (jgarzik's 1.0) || cryppto, Windows 7
|-
| Old Xeon 512k (Dual) || 2x1/2 || 2.0 || || || || 3.0 || cpuminer (v0.8.1-1-g69529c3) || HT disabled, algo=4way (twice as fast as the 2nd best algo)
|-
| Pentium 4 2.0A || 1 || 0.85 || || || || 2.0 || [http://www.bitcoin.org/smf/index.php?topic=3486.0 ufasoft-0.4]/WinXP || -g no -t 2
|-
| Pentium 4 630 || 1/2 || 1.29 || || || || 3.0 || ufasoft 0.23 || Windows XP
|-
| Pentium Dual-Core E2180 || 2/2 || 1.75 || || || || 2.0 || rpcminer-cpu || Win7-64
|-
| Pentium Dual-Core E2180 || 2/2 || 4.1 || || || || 2.0 || cpuminer || sse2_64
|-
| Pentium Dual-Core E2180 || 2/2 || 4.5 || || || || 2.0 || ufasoft v0.11 || Win7-64
|-
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || || 65 || 2.7 || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]
|-
| Celeron E330 || 2/2 || 2.2 || 0.03 || || 65 || 2.5 || 0.3.19/Ubuntu10.04 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37620#msg37620 source]
|-
|-
| Celeron E3400 || 2/2 || 5.9 || - || - || - || 2.6 || Ufasoft v0.13 / GUIMiner v2011-06-14 || WinXP 32 bit, SSE2, Flags "-g no"
|-
| Core 2 Quad Q6600 || 4/4 || 11.0 || || 0.02/0.06 || 105 || 2.40 || bitcoin-miner 0.10 || -a 60 -g no -t 4
|-
| Core 2 Quad Q8200 || 4/4 || 10.9 || || 0.06/0.10 || || 2.33 || Ufasoft 0.14 || -g no -l yes -t 4
|-
| Core 2 Quad Q9400 || 4/4 || 11 || 0.046 || 0.06/0.07 || 95 || 2.66 || bitcoin-miner 0.10 || -a 60 -g no -t 4
|-
| Core 2 Quad Q9650 || 4/4 || 18.67 || || 0.05/0.06 || 95 || 4.00 || bitcoin-miner 0.10 || -a 60 -g no -t 4
|-
| Core i3 530 || 2/4 || 8.31 || 0.10 || 0.06/0.10 || 80 || 3.66 || Ufasoft 0.7 || -v -a5 -g no -t 4
|-
| Core i3 M350 || 2/4 || 1.48 || 0.04 || || 35 || 2.27 || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]
|-
| Core i3-2100 || 2/4 || 8.28 || || || || 3.1 || ufasoft v0.20 ||
|-
| Core i5 M450 || 2/4 || 1.8 || 0.05 || || 35 || 1.2 || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]
|-
| Core i5-650 || 2/4 || 5.1 || 0.04 ? || 0.02/0.03 || || 3.2 || cpuminer-0.7 || -4way
|-
| Core i5-750 || 4/4 || 14 || || 0.06/0.10 || || 3.2 || bitcoin-miner 0.11 || -a 5 -g no -t 4
|-
| Core i5 ? || 4/? || 6.5 || || || || || client from svn || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37621#msg37621 source]
|-
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 0.02/0.03 || 95 || 3.1 || cpuminer git (2011-01-22) || cryptopp_asm32
|-
| Core i5-2400 || 4/4 || 14 || 0.15 || 0.07/0.09 || 95 || 3.1 || cpuminer git (2011-03-26) || sse2_64
|-
| Core i5-2400S || 4/4 || 16.6 || || || 65 || 2.5 || [http://github.com/pooler/cpuminer pooler's cpuminer] 2.2.3 || Linux Mint 13
|-
| Core i5 2500K || 4/4 || 20.6 || ||0.10/0.12 || || 4.2 || bitcoin-miner || -g no
|-
| Core i5 2600K || 4/8 || 17.3 || || || 75 || 3.4 || bitcoin-miner || -g no. 75W for the whole System without monitor (MSI Board). CPU underclocked to 3,4Ghz and undervolted to 1,012Vcore. Passive Cooling! 3.6ghz results in 18,4 Mhash/s
|-
| Core i7 2600K || 4/8 || 18.6 || || || 95 W max. || 3.4 || Ufasoft bitcoin-miner 0.20 || -g no -t 8 CPU @ 3.511Ghz 1.176V
|-
| Core i7 2600 || 4/8 || 23.9 || || || || 3.4 || [http://github.com/pooler/cpuminer pooler's cpuminer] 2.2 || Ubuntu Linux 11.10
|-
| Core i7 620M || 2/4 || 1.888 || || || || 2.66 || [http://forum.bitcoin.org/index.php?topic=8994.0 RPCMiner GUI] v2011-05-22 / Mac OS X 10.6.7 || Model: MacBookPro6,2 RAM: 4GB
|-
| Core i7 620M || 2/4 || 6.5 || || || || 3.33 || This is achieved by running RPC 4 way miner in VMware Fusion 4 (running win 7 in the VM) while in Mac OSX / Mac OS X 10.6.8 || Model: MacBookPro6,2 RAM: 8GB.The CPU appears to turbo boost to 3.33GHz in this way from 2.67GHz when running it in this way.The MBP gets very hot and uses a lot of energy though so watch those temps.It'll throttle after a while unless you keep the air vents clear underneath (ie don't put int in your lap,etc).
|-
| Core i7 720QM || 4/8 || 7.9 || ?|| || 45 || 2.8 || [http://www.bitcoin.org/smf/index.php?topic=3486.0 ufasoft] || stream processors overclocked from 1.6 GHz; Dell Precision M6500, Win7-64, 8GB DDR3
|-
| Core i7 820 || 4/8 || 13.8 || || || || 2.8 || [http://www.bitcoin.org/smf/index.php?topic=3486.0 ufasoft] || -t 8
|-
| Core i7 920 || 4/8 || 19.2 || 0.10 || || 195 || 4.0 (x21) || [http://www.bitcoin.org/smf/index.php?topic=3486.0 ufasoft] || -a 5
|-
| Core i7 950 || 4/8 || 5.88 || 0.039 || || 150 || 3.83 (x23) || bitcoin-0.3.20.2 Win7-64 ||
|-
| Core i7 950 || 4/8 || 18.9 || 0.126 || || 150 || 3.83 (x23) || [http://www.bitcoin.org/smf/index.php?topic=3486.0 ufasoft] v0.4 ||
|-
| Core i7 980x || 6/12 || 19.2 || 0.15 || || 130 || 4.4 (x33) || cpuminer/Win7-64 ||
|-
| Core i7 980x || 6/12 || 8.7 || || || || 3.9 (x27) || 0.3.17/Win7-64 ||
|-
| Core i7 990x || 6/12 || 33.3 || || || || 4.5 (x32) || ufasoft/Win2008 R2-64 || Ram - 12Gb, Rampage III BlackEdition, Water cooling
|-
| Core i7 2635QM || 4/8 || 2.93 || || || || 2.00 || [http://forum.bitcoin.org/index.php?topic=8994.0 RPCMiner GUI] v2011-05-22 / Mac OS X 10.6.7 || Model: MacBookPro8,2 RAM: 4GB
|-
| Core i7 620M || 2/4 || 6.3 || 0.18 || || 35 || 2.66 || [http://www.bitcoin.org/smf/index.php?topic=3486.0 ufasoft] v0.4 ||
|-
| Core i7 2600k || 4/4 || 6.7 || || || || 4.00 || phoenix 0.48 ||
|-
| Core i7 3770k || 4/8 || 5.2 || || || || 4.4 || Guiminer v2012-12-03 || Windows 7 x64 : -v argument increased Mhash/s from 5.0 to 5.2
|-
| Core i7 3930k || 6/12 || 66.6 || || || || 4.625 (125 x 37) || Ufasoft bitcoin-miner v0.28 || Windows 7 x64, uses ~190watts : -v argument increased Mhash/s from 36.0 to 66.6
|-
| Core 2 Duo U7600 || 1 || 1.1 || || || || 1.2 || minerd (jgarzik's 1.0) || cryppto, Windows 7
|-
| Core 2 Duo E5200 || 2/2 || 6.2 || 0.086 || || 72 || 2.76 || Ufasoft/Win7-64 || TDP is 65W + 7W overclock
|-
| Core 2 Duo E6550 || 1/2 || 2.45 || || || || 2.33 || cpuminer 0.7.1 (Linux) || --algo=sse2_64
|-
| Core 2 Duo E6850 || 2/2 || 6.75 || 0.10 || || 65 || 3.0 || ufasoft-0.3 ||
|-
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || || 70 || 3.33 || ufasoft-0.3 || uncertain of overclock; miner optimized for Intel Core
|-
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || || 65 || 2.66 || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]
|-
| Core 2 Duo E8200 || 2/2 || 2.3 || 0.035 || || 65 || 2.66 || rpcminer-cpu ||
|-
| Core 2 Duo E8400 || 2/2 || 6.9 || 0.106 || || 65 || 3.0 || ufasoft v0.10 || windows 7/64bit (-t 2)
|-
| Core 2 Duo E8500 || 1/2 || 3.6 || || || || 3.16 || guiminer v2011-06-14 || windows vista 32bit
|-
| Core 2 Duo E8500 || 2/2 || 7.2 || || || || 3.16 || guiminer v2011-06-14 || windows vista 32bit
|-
| Core 2 Duo P8700 || 2/2 || 5.9 || || || || 2.53 || ufasoft v0.21 || windows 7/64bit
|-
| Core 2 Duo T5450 || 2/2 || 2.5 || 0.07 || || 35 || 1.63 || bitcoin-miner 0.10 || Ubuntu 11.04
|-
| Core 2 Duo T5500 || 2/2 || 4.3 || || || || 1.66 || [http://github.com/pooler/cpuminer pooler's cpuminer] 2.2 || Gentoo Linux (amd64)
|-
| Core 2 Duo T6400 || 2/2 || 4.2 || 0.12 || || 35 || 2.00 || cpuminer git (Linux) || --algo=sse2_64
|-
| Core 2 Duo T7250 || 2/2 || 4.5 || 0.13 || || 35 || 2.00 || bitcoin-miner 0.13/WinXP || No GPU
|-
| Core 2 Duo T7450 || 2/2 || 3.7 || 0.10 || || 35 || 2.13 || bitcoin-miner 0.10 || Ubuntu 11.04
|-
| Core 2 Duo T9400 || 2/2 || 4.2 || || || || 2.53 || ufasoft v0.13 || Win7-64
|-
| Core 2 Extreme X9000 || 2/2 || 2.37 || || || || 2.8 || rpcminer-cpu || Win7-64
|-
| Core 2 Extreme X9000 || 2/2 || 6.2 || || || || 2.8 || ufasoft v0.11 || Win7-64
|-
| Core 2 Extreme X9000 || 2/2 || 7.2 || || || || 3.2 || ufasoft v0.11 || Win7-64 Overclocked from 2.8 GHz to 3.2 GHz
|-
| Xeon 2.8 || 2/2 || 0.8 || || || || 2.8 || cpuminer || cryptopp_asm32
|-
| Xeon 3060 || 1/2 || 2.03 || 0.03 || || 65 || 2. || cpuminer 0.8.1 (Linux) || --algo=cryptopp_asm32
|-
| Xeon Prestonia 2.4 (dual) || 2x1/2 || 2.16 || 0.017 || || 130 || 2.4 || ufasoft v0.4 ||
|-
| Xeon X5355 (dual) || 2x4/4 || 10.13 || 0.16 || || 120 || 2.6 || bitcoind || Roughly the same speed as the "c" algo in cpuminer
|-
| Xeon E3-1230 V2 (quad) || 4/8 || 19.7 || ? || ? || ? || 3.70 || cgminer 2.8.3 || -O2 -march=core-avx-i algo=sse2_64
|-
| Xeon X5355 (dual) || 2x4/4 || 22.76 || 0.09 || || 120 || 2.6 || cpuminer (v0.8.1-1-g69529c3) || -O2 -march=core2, algo=sse2_64
|-
| Xeon X5365 (dual) || 2x4/4 || 26.00 || ? || || ? || 3.0 || cpuminer git (2011-06-15) || algo=sse2_64
|-
| Xeon X5650 || 2x6/24 || 28.6 || ? || ? || ? || 2.67 || cpuminer 1.0.2 || --algo 4way
|-
| Xeon x5680 (dual) || 2x6/24 || 48 || ? || ? || ? || 3.33GHz || Ufasoft 0.29 || CentOS 6.2 x86_64
|-
| Xeon x5690 (dual) || 2x6/24 || 52 || ? || ? || ? || 3.46GHz || Ufasoft 0.29 || CentOS 6.2 x86_64
|-
| Xeon E5-2690 (dual) || 2x8/32 || 66 || ? || ? || 2x135W || 2.9GHz || Ufasoft 64-bit 0.31 || Windows Server 2008R2 x64
|-
| Xeon E5335 || 4/4 || 9.35 || 0.12 || || 80 || 2.00 || ufasoft v0.11 || Vista-32
|-
| Xeon E5410 || 4/4 || 9.8 || ? || || 80 || 2.33|| ufasoft v0.10 || CentOS 5.5 x64
|-
| Xeon E5440 || 4/8 || 7.3 || ? || || 80 || 2.66|| Kiv's poclbm-gui || FIXME: Either wrong model # or wrong threads/speed info
|-
| Xeon E5506 || 4/4 || 9.6 || ? || || 80 || 2.13|| ufasoft v0.10 || CentOS 5.5 x64
|-
| Xeon E5520 || 4/8 || 6.5 || 0.08 || || 80 || 2.27 || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]
|-
| Xeon E5530 || 4/8 || 7.14 || 0.09 || || 80 || 2.4 || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]
|-
| Xeon E5620 || 4/8 || 11.2 || ? || || 80 || 2.4 || ufasoft v0.10 -t 4 || CentOS 5.5 x64 Hyper-Threading is off
|-
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || || 80 || 2.53 || 0.3.17/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]
|-
| Xeon E6520 (dual) || 2x4/8 || 24.7 || || || || 2.53 || ufasoft v0.10 || windows 2008 R2 64bit (-t 16)
|-
| Xeon E7220 || 2/2 || 6.3 || ? || || 80 || 2.93|| ufasoft v0.10 || CentOS 5.5 x64
|-
| Xeon E7320 (dual) || 2x2 || 1.5 || || || || 2.8 || cgminer v1.2.8 || 2x2.8ghz dual core running Ubuntu 11.04 x86 (individual cores get 0.4 MH/s)
|-
| Xeon E7450 (quad) || 4x6/24 || 60 || || || || 2.40 || ufasoft v0.13 || -t 24
|-
| Xeon E7520 (dual) || 2x4/16 || 18 || || || 95 || 1.87 || ufasoft v0.10 || windows 2008 R2 64bit (-t 16)
|-
| Xeon W3680 || 6/12 || 18 || || || 130 || 3.33 || cpuminer v1.0.2 --algo=4way || Ubuntu 11.04 64bit
|-
| Atom Z520 || 1/2 || 1.20 || || || 2 || 1.7 || ufasoft 1.18 || Asus Eee 1101HA with overclocking capabilities
|-
| Atom N230 || 1/2 || 0.375 || || || 4 || 1.6 || rpcminer-cpu ||
|-
| Atom N230 || 1/2 || 0.245 || || || 4 || 1.6 || rpcminer-4way ||
|-
| Atom N230 || 1/2 || 0.97 || || || 4 || 1.6 || ufasoft v0.10 ||
|-
| Atom N270 || 1/2 || 1.19 || 0.24 || || 5 || 1.6 || ufasoft v0.10 ||
|-
| Atom N450 || 1/2 || 1.60 || 0.31 || || 6.5 || 2.06 || ufasoft v0.10 ||
|-
| Atom N550 || 2/4 || 1.97 || || || || 1.5 || ufasoft v0.21 || Windows 7/64 bit
|-
| Atom 330 || 2/4 || 1.80 || || || 8 || 1.6 || ufasoft v0.13 || -t 4
|-
| Atom D510 || 2/4 || 1.00 || || || || 1.6 || cpuminer w cryptopp_asm32 || debian linux 6.0, headless system, 2 GB RAM, running from usb-flash
|-
| Atom D510 || 4/4 || 2.3 || 0.07 || || 30 || 1.6 || bitcoin-miner 0.10 || Ubuntu 11.04 Server
|-
| Xeon Phi 5100 || 60/240 || 140 || || || || 1.053 || [https://github.com/kiyominer/cpuminer pooler's cpuminer port] || native mode
|}

<references>
<ref name='amazon_20110625'>$ Prices from http://www.amazon.com on 2011-06-25</ref>
<ref name='geizhals_20110625'>€ Prices from http://geizhals.at/eu on 2011-06-25</ref>
</references>

===Other===
{| class="wikitable sortable"
|-
! Model !! p/t !! Mhash/s !! Mhash/J !! Mhash/s/$ !! ACP [W] !! Clock !! Version !! Comment
|-
| Cell || 6 || 21 || 0.35 || 0.07 || 60W || 3.2 GHz || Cellminer || Sony Playstation 3 (FAT): Needs custom firmware. [https://github.com/verement/cellminer source] [http://www.bitcoin.org/smf/index.php?topic=4704.20 source] Total power usage of PS3 fat is 120W but only the Cell cpu is active.
|-
| Cell || 7 || 26.6 || ? || ? || 60W || 3.2 GHz || Cellminer || Sony Playstation 3 (FAT): Needs custom firmware. [https://github.com/verement/cellminer source] [http://www.bitcoin.org/smf/index.php?topic=4704.20 source] Running with 7th spu enabled and both ppe cores.
|-
| Cell || 6 || 21 || 0.7 || 0.07 || 35W || 3.2 GHz || cellminer || Sony Playstation 3 (SLIM): Total power usage of PS3 slim is 70W but only the Cell cpu is active.
|-
| MIPS || 1 || 0.026 || ? || ? || ? || 200 MHz || cpuminer || ASUS WL-500G Deluxe Router Running [http://openwrt.org/ OpenWrt]
|-
| VIA Eden || 1 || 1.3 || 0.17 || || 8W || 1600 MHz || cpuminer || VIA Eden w/ padlock
|-
| PowerPC 7447A || 1 || 0.53 || || || || 1420 MHz || cpuminer ||
|-
| PowerPC 7450 (G4e) || 1 || 1.29 || || || || 1670 MHz || cgminer 2.0.7 || PowerBook5,6; Mac OS X 10.5.8; Altivec
|-
| PowerPC 750 (G3) || 1 || 0.140 || || || || 600 MHz || cpuminer || iBook G3 600 w/ Cryptopp
|-
| IBM POWER4+ 2/way || 2/1 || 0.58 || || || || 1450 MHz || cpuminer 2.2.3 || CRUX PPC (64bit), cpuminer -a sha256d -t 1
|-
| IBM Power7 (PowerPC) || || 7.6 || || || || 3.5 Ghz || cgminer || IBM Power7 770, SuSE Linux 11.1, 4 cores, OpenCL, YASM, Altivec
|-
| Google App Engine || 1 || 0.144 || || || 0W || || pyminer || Modified version of [https://github.com/jgarzik/pyminer pyminer] for GAE.
|-
| Open Shift || 1 || 0.059 || || || 0W || || pyminer ||
|}

<references></references>

==See Also==
* [[TP's Bitcoin Calculator]]
* [[Mining rig]]
* [[ZTEX FPGA Boards for Bitcoin Mining]]
* [[Generation Calculator]]
* [[Power Calc]]
* [[OpenCL miner]]
* [http://www.pcper.com/article.php?aid=745 ATI Stream vs. NVIDIA CUDA - GPGPU computing battle royale]
* [https://www.weusecoins.com/en/mining-guide/ Getting Started With Bitcoin Mining]
* [http://bitminer.info/ Bitminer.info]
* [http://www.pcper.com/reviews/Graphics-Cards/Bitcoin-Currency-and-GPU-Mining-Performance-Comparison Bitcoin Mining Performance Compared]
* [http://www.pcper.com/reviews/Graphics-Cards/Bitcoin-Mining-Update-Power-Usage-Costs-Across-United-States Bitcoin Mining Power Costs Compared]
* [https://www.bitcoinmining.com/ Bitcoin Mining]
* [https://www.bitcoinmining.com/bitcoin-mining-hardware/ Bitcoin Mining Hardware]
[[Category:Mining]]
[[Category:Hardware]]

Mining rig

2015-08-04T14:20:52Z

Sunnankar: /* See Also */

A '''mining rig''' is a computer system used for [[How_bitcoin_works#Bitcoin_mining|mining bitcoins]]. The rig might be a dedicated miner where it was procured, built and operated specifically for mining or it could otherwise be a computer that fills other needs, such as performing as a gaming system, and is used to mine only on a part-time basis.

'''Warning:''' GPU mining is not very profitable (if at all) anymore, and even if you have free electricity, GPU rigs will likely never pay for themselves at this point!

[[{{ns:file}}:Quick-and-dirty-4x5970-cooling.jpg|thumb|4x5970 Mining rig http://blog.zorinaq.com/?e=47]]
==Tips==

* Motherboards with on-board graphics (also referred to as integrated graphics) often are either problematic or unusable when more than one GPU card is installed. Choose a motherboard with no on-board graphics.
* The following component lists might be used to help in building a new rig. To minimize shipping costs, components from the same supplier were preferred over compenents from the least expensive source.

==Typical Dedicated Miner Configurations Using a Tower==

===One ATI 5830, Approximately 245 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || n/a || n/a || n/a
|-
| Power Supply || Rosewill Green Series RG530-S12 530W, 80 PLUS Certified || [http://www.newegg.com/Product/Product.aspx?Item=N82E16817182199 NewEgg] || $50
|-
| Motherboard || Foxconn M61PMP-K AMD || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813186189&Tpk=m61pmp NewEgg] || $45
|-
| CPU || AMD Sempron 145 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888 NewEgg] || $39
|-
| Memory || 2GB DDR3 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820146744 NewEgg] || $13
|-
| Graphics card || Radeon HD 5830 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16814102878 NewEgg] ($153) || $110
|-
| Case Fan || n/a || n/a || n/a
|-
| Storage || Western Digital Caviar 80GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822136292 NewEgg] || $17
|-
| Media Drive || DVD Rom Drive || n/a || n/a
|-
| Keyboard, Mouse and Display || n/a || n/a || n/a
|-
| Total || (Approx: $1.1755 /Mhash) || || $285 + s/h/t
|}

===Three ATI 5770s, Approximately 630 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Power Supply || Rosewill Green Series RG530-S12 530W, 80 PLUS Certified || [http://www.newegg.com/Product/Product.aspx?Item=N82E16817182199 NewEgg] || $50
|-
| Motherboard || ASRock 890GX EXTREME4 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813157207 NewEgg] || $125
|-
| CPU || AMD Sempron 145 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888 NewEgg] || $39
|-
| Memory || 2GB DDR3 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820146744 NewEgg] || $13
|-
| Graphics card || Sapphire Radeon HD5770 1GB DDR5 || [http://www.superbiiz.com/detail.php?name=AT-5770V3&title=Sapphire-Radeon-HD5770-1GB-DDR5-2DVI-HDMI-DisplayPort-PCI-Express-Video-Card superbiiz] || $339 ($113 x 3)
|-
| Storage || Western Digital Caviar 80GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822136292 NewEgg] || $17
|-
| Total || (Approx: $1.0412 /Mhash) || || $583 + s/h/t
|}

===Two ATI 5850s, Approximately 600 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || n/a || n/a || n/a
|-
| Power Supply || CORSAIR Builder Series CX600 V2 600W , 80 PLUS Certified || [http://www.newegg.com/Product/Product.aspx?Item=N82E16817139028 NewEgg] || $70
|-
| Motherboard || MSI 870-G45 AM3 AMD 770 ATX || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813130290 NewEgg ($5 more)] || $70
|-
| CPU || AMD Sempron 145 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888 NewEgg] || $39
|-
| Memory || 2GB DDR3 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820146744 NewEgg] || $13
|-
| Graphics card || Sapphire Radeon HD 5850 XTREME || $322 ($161 x 2)
|-
| Case Fan || n/a || n/a || n/a
|-
| Storage || Western Digital Caviar 80GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822136292 NewEgg] || $17
|-
| Media Drive || DVD Rom Drive || n/a || n/a
|-
| Keyboard, Mouse and Display || n/a || n/a || n/a
|-
| Total || (Approx: $0.8917 /Mhash) || || $531 + s/h/t
|}

===Three ATI 5850s, Approximately 900 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || n/a || n/a || n/a
|-
| Power Supply || PC Power & Cooling Silencer Mk II 950W, 80 PLUS Silver Certified || [http://www.directron.com/ppcmk2s950.html Directron] || $120
|-
| Motherboard || MSI 890FXA-GD70 || || $195
|-
| CPU || AMD Sempron 145 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888 NewEgg] || $39
|-
| Memory || 2GB DDR3 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820146744 NewEgg] || $13
|-
| Graphics card || Sapphire Radeon HD 5850 XTREME || || $483 ($161 x 3)
|-
| Case Fan || n/a || n/a || n/a
|-
| Storage || Western Digital Caviar 80GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822136292 NewEgg] || $17
|-
| Media Drive || DVD Rom Drive || n/a || n/a
|-
| Keyboard, Mouse and Display || n/a || n/a || n/a
|-
| Total || (Approx: $0.9677 /Mhash) || || $877 + s/h/t
|}

===Three ATI 6990s, Approximately 2.1 Ghash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || CoolerMaster HAF X || || $179
|-
| Power Supply || SILVERSTONE ST1500 1500W, 80 PLUS Silver Certified || [http://www.newegg.com/Product/Product.aspx?Item=N82E16817256054&Tpk=silverstone%201500w Newegg] || $365
|-
| Motherboard || MSI 890FXA-GD70 || || $195
|-
| CPU || AMD Sempron 145 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888 NewEgg] || $39
|-
| Memory || 2GB DDR3 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820146744 NewEgg] || $13
|-
| Graphics card || 3 * Radeon HD 6990 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16814125370&cm_re=6990-_-14-125-370-_-Product NewEgg] || $2220 ($740 × 3)
|-
| Storage || Western Digital Caviar 80GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822136292 NewEgg] || $17
|-
| Keyboard, Mouse and Display || n/a
|-
| Total || (Approx: $1.4438 /Mhash) || || $3,028 + s/h/t
|}

==Typical Dedicated Miner Configurations Using a Rack Mount==

===Budget AMD Sempron / Dual ATI 6990: Approximately 1.4 Ghash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || IPC-4370S 4U || [http://www.plinkusa.net/web4038.htm P-Link Computer] || $85 (incl s/h)
|-
| Power Supply || PC Power & Cooling Silencer Mk II 950W, 80 PLUS Silver Certified || [http://www.directron.com/ppcmk2s950.html Directron] || $120
|-
| Motherboard || MSI 870-G45 AM3 AMD 770 ATX || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813130290 NewEgg ($5 more)] || $70
|-
| CPU || AMD Sempron 145 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888 NewEgg] || $39
|-
| Memory || 2GB DDR3 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820146744 NewEgg] || $13
|-
| Graphics card || 2 * Radeon HD 6990 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16814125370&cm_re=6990-_-14-125-370-_-Product NewEgg] || $1480 ($740 × 2)
|-
| Storage || Western Digital Caviar 80GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822136292 NewEgg] || $17
|-
| Keyboard, Mouse and Display || n/a
|-
| Total || (Approx: $1.3057 /Mhash) || || $1,824 + s/h/t
|}

==Typical Multipurpose Miner Configurations==

===High-end Intel-based miner/gaming rig: single ATI 6990, Approximately 750 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || CoolerMaster HAF 932 || || $140
|-
| Power Supply || PC Power & Cooling Silencer Mk II 950W, 80 PLUS Silver Certified || [http://www.directron.com/ppcmk2s950.html Directron] || $120
|-
| Motherboard || MSI P67A-GD65 || || $173
|-
| CPU || Intel Core i7-2700K || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819115095 NewEgg] || $340
|-
| Memory || G.SKILL ECO Series 8GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820231403 NewEgg] || $55
|-
| Graphics card || Radeon HD 6990 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16814150529&cm_re=6990-_-14-150-529-_-Product NewEgg] || $734
|-
| Heat Sink Fan || CoolerMaster Hyper212+ || [http://www.newegg.com/Product/Product.aspx?Item=N82E16835103065&cm_re=hyper_212-_-35-103-065-_-Product NewEgg] || $40
|-
| Storage || Seagate 1TB 7200RPM HDD || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822148433 NewEgg] || $70
|-
| Media Drive || ASUS DVD-RW || [http://www.newegg.com/Product/Product.aspx?Item=N82E16827135204 NewEgg] || $22
|-
| Keyboard || LITE-ON SK-1788/BS PS/2 Keyboard || [http://www.newegg.com/Product/Product.aspx?Item=N82E16823107120 NewEgg] || $8
|-
| Mouse || V7 M30P20-7N PS/2 Mouse || [http://www.newegg.com/Product/Product.aspx?Item=N82E16826575002 NewEgg] || $7
|-
| Display || LG IPS231P-BN Black 23" 6ms IPS || [http://www.newegg.com/Product/Product.aspx?Item=N82E16824005234 NewEgg] || $250
|-
| Total || || || $1949 + s/h/t
|}

===High-end AMD-based miner/gaming rig: single ATI 6990, Approximately 750 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || CoolerMaster HAF 932 || || $140
|-
| Power Supply || PC Power & Cooling Silencer Mk II 950W, 80 PLUS Silver Certified || [http://www.directron.com/ppcmk2s950.html Directron] || $120
|-
| Motherboard || Biostar TA990FXE || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813138341 NewEgg] || $130
|-
| CPU || AMD FX-8150 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819103960 NewEgg] || $250
|-
| Memory || G.SKILL ECO Series 8GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820231403 NewEgg] || $55
|-
| Graphics card || Radeon HD 6990 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16814150529&cm_re=6990-_-14-150-529-_-Product NewEgg] || $734
|-
| Heat Sink Fan || CoolerMaster Hyper212+ || [http://www.newegg.com/Product/Product.aspx?Item=N82E16835103065&cm_re=hyper_212-_-35-103-065-_-Product NewEgg] || $40
|-
| Storage || Seagate 1TB 7200RPM HDD || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822148433 NewEgg] || $70
|-
| Media Drive || ASUS DVD-RW || [http://www.newegg.com/Product/Product.aspx?Item=N82E16827135204 NewEgg] || $22
|-
| Keyboard || LITE-ON SK-1788/BS PS/2 Keyboard || [http://www.newegg.com/Product/Product.aspx?Item=N82E16823107120 NewEgg] || $8
|-
| Mouse || V7 M30P20-7N PS/2 Mouse || [http://www.newegg.com/Product/Product.aspx?Item=N82E16826575002 NewEgg] || $7
|-
| Display || LG IPS231P-BN Black 23" 6ms IPS || [http://www.newegg.com/Product/Product.aspx?Item=N82E16824005234 NewEgg] || $250
|-
| Total || || || $1832 + s/h/t
|}

===Mid-level AMD-based miner/gaming/workstation rig: single ATI 6870, Approximately 300 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || CoolerMaster Centurion 5 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16811119068 NewEgg] || $50
|-
| Power Supply || Antec Earthwatts EA-650 GREEN 650W, 80 PLUS BRONZE certified || [http://www.newegg.com/Product/Product.aspx?Item=N82E16817371044 NewEgg] || $65
|-
| Motherboard || MSI 970A-G46 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813130637 NewEgg] || $90
|-
| CPU (incl. stock heatsink + fan)|| AMD FX-6200 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819106010 NewEgg] || $169
|-
| Memory || G.SKILL Value Series 4GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820231396 NewEgg] || $23
|-
| Graphics card || Radeon HD 6870 || || $165
|-
| Storage || Seagate 1TB 7200RPM HDD || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822148433 NewEgg] || $70
|-
| Media Drive || ASUS DVD-RW || [http://www.newegg.com/Product/Product.aspx?Item=N82E16827135204 NewEgg] || $21
|-
| Keyboard || LITE-ON SK-1788/BS PS/2 Keyboard || [http://www.newegg.com/Product/Product.aspx?Item=N82E16823107120 NewEgg] || $8
|-
| Mouse || V7 M30P20-7N PS/2 Mouse || [http://www.newegg.com/Product/Product.aspx?Item=N82E16826575002 NewEgg] || $7
|-
| Display || HANNspree By Hanns-G HF225DPB 21.5" || [http://www.newegg.com/Product/Product.aspx?Item=N82E16824262011 NewEgg] || $120
|-
| Total || || || $798 + s/h/t
|}

===Mid-level Intel-based miner/gaming/workstation rig: single ATI 6870, Approximately 300 Mhash/s===

{| class="wikitable"
|-
! Component !! Description !! Source !! Amount
|-
| Chassis || CoolerMaster Centurion 5 || [http://www.newegg.com/Product/Product.aspx?Item=N82E16811119068 NewEgg] || $50
|-
| Power Supply || Antec Earthwatts EA-650 GREEN 650W, 80 PLUS BRONZE certified || [http://www.newegg.com/Product/Product.aspx?Item=N82E16817371044 NewEgg] || $65
|-
| Motherboard || MSI Z68A-G45 (B3) || [http://www.newegg.com/Product/Product.aspx?Item=N82E16813130618R NewEgg] || $103
|-
| CPU (incl. stock heatsink + fan)|| Intel Core i5-2500K || [http://www.newegg.com/Product/Product.aspx?Item=N82E16819115072 NewEgg] || $214
|-
| Memory || G.SKILL Value Series 4GB || [http://www.newegg.com/Product/Product.aspx?Item=N82E16820231396 NewEgg] || $23
|-
| Graphics card || Radeon HD 6870 || || $165
|-
| Storage || Seagate 1TB 7200RPM HDD || [http://www.newegg.com/Product/Product.aspx?Item=N82E16822148433 NewEgg] || $70
|-
| Media Drive || ASUS DVD-RW || [http://www.newegg.com/Product/Product.aspx?Item=N82E16827135204 NewEgg] || $21
|-
| Keyboard || LITE-ON SK-1788/BS PS/2 Keyboard || [http://www.newegg.com/Product/Product.aspx?Item=N82E16823107120 NewEgg] || $8
|-
| Mouse || V7 M30P20-7N PS/2 Mouse || [http://www.newegg.com/Product/Product.aspx?Item=N82E16826575002 NewEgg] || $7
|-
| Display || HANNspree By Hanns-G HF225DPB 21.5" || [http://www.newegg.com/Product/Product.aspx?Item=N82E16824262011 NewEgg] || $120
|-
| Total || || || $873 + s/h/t
|}

==See Also==

* [[Mining Hardware Comparison]]
* [http://coinminingrigs.com/ GPU Rig Assembly Guides]
* [https://www.weusecoins.com/en/mining-guide/ Getting Started With Bitcoin Mining]
* [https://www.bitcoinmining.com Bitcoin Mining]
* [https://www.youtube.com/watch?v=GmOzih6I1zs Video: What is Bitcoin Mining?]
* [http://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ Research, Review and Compare Cloud Mining Contracts]
* [http://bitminer.info/ Bitminer.info]
* [https://rigsmonitoring.com/ RigsMonitoring]

[[Category:Mining]]

Bit Gold proposal

2015-07-18T00:32:08Z

Sunnankar: /* References */

The Bit Gold proposal, by Nick Szabo, describes a system for the decentralized creation of unforgeable chains of [[proof of work|proofs of work]], with each one being attributed to its discoverer's public key, using timestamps and digital signatures. It is said that these proofs of work would have value because they would be scarce, difficult to produce, and securely stored and transferred. Szabo's theory of the economics of such money is described in the linked article on [http://szabo.best.vwh.net/shell.html the origins of money].

Transfer with prevention of [[double-spending]], via a Byzantine-resilient peer-to-peer method, is described in another linked article which calls the method [http://szabo.best.vwh.net/securetitle.html secure property titles] and proposes also applying it to other kinds of digital property, such as domain names. However, this Byzantine method relies on a ''quorum of network addresses'' rather than a ''quorum of (hash) computing power'', so unlike bitcoin it is vulnerable to [http://en.wikipedia.org/wiki/Sybil_attack Sybil attacks].

==References==
* [http://unenumerated.blogspot.com/2005/12/bit-gold.html Bit gold]
* [http://szabo.best.vwh.net/securetitle.html Secure property titles with owner authority]
* [http://szabo.best.vwh.net/shell.html The origins of money]
* [http://www.runtogold.com/goldmoney/bitgold-review/ Bitgold Review] - Not related to Szabo's Bitgold whatsoever.
* [https://www.weusecoins.com/bitgold/ Bitgold Review]

Difficulty

2015-07-13T18:56:47Z

Sunnankar: /* Related Links */

''See also: [[target]]''

=== What is "difficulty"? ===

Difficulty is a measure of how difficult it is to find a hash below a given target.

The Bitcoin network has a global block difficulty. Valid blocks must have a hash below this target.
Mining pools also have a pool-specific share difficulty setting a lower limit for shares.

=== How often does the network difficulty change? ===

Every 2016 [[block|blocks]].

=== What is the formula for difficulty? ===

difficulty = difficulty_1_target / current_target

(target is a 256 bit number)

difficulty_1_target can be different for various ways to measure difficulty.
Traditionally, it represents a hash where the leading 32 bits are zero and the rest are one (this is known as "pool difficulty" or "pdiff").
The Bitcoin protocol represents targets as a custom floating point type with limited precision; as a result, Bitcoin clients often approximate difficulty based on this (this is known as "bdiff").

===How is difficulty stored in blocks?===

Each block stores a packed representation (called "Bits") for its actual hexadecimal [[target]]. The target can be derived from it via a predefined formula. For example, if the packed target in the block is 0x1b0404cb, the hexadecimal target is
0x0404cb * 2**(8*(0x1b - 3)) = 0x00000000000404CB000000000000000000000000000000000000000000000000

Note that the 0x0404cb value is a signed value in this format. The largest legal value for this field is 0x7fffff. To make a larger value you must shift it down one full byte. Also 0x008000 is the smallest positive valid value.

===How is difficulty calculated? What is the difference between bdiff and pdiff?===

The highest possible target (difficulty 1) is defined as 0x1d00ffff, which gives us a hex target of
0x00ffff * 2**(8*(0x1d - 3)) = 0x00000000FFFF0000000000000000000000000000000000000000000000000000

It should be noted that pooled mining often uses non-truncated targets, which puts "pool difficulty 1" at
0x00000000FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF

So the difficulty at 0x1b0404cb is therefore:
0x00000000FFFF0000000000000000000000000000000000000000000000000000 /
0x00000000000404CB000000000000000000000000000000000000000000000000
= 16307.420938523983 (bdiff)
And:
0x00000000FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF /
0x00000000000404CB000000000000000000000000000000000000000000000000
= 16307.669773817162 (pdiff)

Here's a fast way to calculate bitcoin difficulty. It uses a modified Taylor series for the logarithm (you can see tutorials on flipcode and wikipedia) and relies on logs to transform the difficulty calculation:

<source lang="cpp">
#include <iostream>
#include <cmath>

inline float fast_log(float val)
{
int * const exp_ptr = reinterpret_cast <int *>(&val);
int x = *exp_ptr;
const int log_2 = ((x >> 23) & 255) - 128;
x &= ~(255 << 23);
x += 127 << 23;
*exp_ptr = x;

val = ((-1.0f/3) * val + 2) * val - 2.0f/3;
return ((val + log_2) * 0.69314718f);
}

float difficulty(unsigned int bits)
{
static double max_body = fast_log(0x00ffff), scaland = fast_log(256);
return exp(max_body - fast_log(bits & 0x00ffffff) + scaland * (0x1d - ((bits & 0xff000000) >> 24)));
}

int main()
{
std::cout << difficulty(0x1b0404cb) << std::endl;
return 0;
}
</source>

To see the math to go from the normal difficulty calculations (which require large big ints bigger than the space in any normal integer) to the calculation above, here's some python:

<source lang="python">
import decimal, math
l = math.log
e = math.e

print 0x00ffff * 2**(8*(0x1d - 3)) / float(0x0404cb * 2**(8*(0x1b - 3)))
print l(0x00ffff * 2**(8*(0x1d - 3)) / float(0x0404cb * 2**(8*(0x1b - 3))))
print l(0x00ffff * 2**(8*(0x1d - 3))) - l(0x0404cb * 2**(8*(0x1b - 3)))
print l(0x00ffff) + l(2**(8*(0x1d - 3))) - l(0x0404cb) - l(2**(8*(0x1b - 3)))
print l(0x00ffff) + (8*(0x1d - 3))*l(2) - l(0x0404cb) - (8*(0x1b - 3))*l(2)
print l(0x00ffff / float(0x0404cb)) + (8*(0x1d - 3))*l(2) - (8*(0x1b - 3))*l(2)
print l(0x00ffff / float(0x0404cb)) + (0x1d - 0x1b)*l(2**8)
</source>

=== What is the current difficulty? ===
[http://blockexplorer.com/q/getdifficulty Current difficulty], as output by Bitcoin's getDifficulty.

[http://blockexplorer.com/q/estimate Estimated next difficulty]

[http://bitcoin.sipa.be Graphs]

=== What is the maximum difficulty? ===

There is no minimum target. The maximum difficulty is roughly: maximum_target / 1 (since 0 would result in infinity), which is a ridiculously huge number (about 2^224).

The actual maximum difficulty is when current_target=0, but we would not be able to calculate the difficulty if that happened. (fortunately it never will, so we're ok.)

=== Can the network difficulty go down? ===
Yes it can. See discussion in [[target]].

=== What is the minimum difficulty? ===
The minimum difficulty, when the target is at the maximum allowed value, is 1.

=== What network hash rate results in a given difficulty? ===
The difficulty is adjusted every 2016 blocks based on the [[Block_timestamp|time]] it took to find the previous 2016 blocks. At the desired rate of one block each 10 minutes, 2016 blocks would take exactly two weeks to find. If the previous 2016 blocks took more than two weeks to find, the difficulty is reduced. If they took less than two weeks, the difficulty is increased. The change in difficulty is in proportion to the amount of time over or under two weeks the previous 2016 blocks took to find.

To find a block, the hash must be less than the target. The hash is effectively a random number between 0 and 2**256-1. The offset for difficulty 1 is
0xffff * 2**208
and for difficulty D is
(0xffff * 2**208)/D

The expected number of hashes we need to calculate to find a block with difficulty D is therefore
D * 2**256 / (0xffff * 2**208)
or just
D * 2**48 / 0xffff

The difficulty is set such that the previous 2016 blocks would have been found at the rate of one every 10 minutes, so we were calculating (D * 2**48 / 0xffff) hashes in 600 seconds. That means the hash rate of the network was
D * 2**48 / 0xffff / 600
over the previous 2016 blocks. Can be further simplified to
D * 2**32 / 600
without much loss of accuracy.

At difficulty 1, that is around 7 Mhashes per second.

At the time of writing, the difficulty is 22012.4941572, which means that over the previous set of 2016 blocks found the average network hash rate was
22012.4941572 * 2**32 / 600 = around 157 Ghashes per second.

=== How soon might I expect to generate a block? ===
(The [https://www.bitcointalk.org/index.php?topic=1682.0 eternal question].)

The average time to find a block can be approximated by calculating:
time = difficulty * 2**32 / hashrate
where difficulty is the current difficulty, hashrate is the number of hashes your miner calculates per second, and time is the average in seconds between the blocks you find.

For example, using Python we calculate the average time to generate a block using a 1Ghash/s mining rig when the difficulty is 20000:
$ python -c "print 20000 * 2**32 / 10**9 / 60 / 60.0"
23.85
and find that it takes just under 24 hours on average.

* Any one grinding of the hash stands the same chance of "winning" as any other. The numbers game is how many attempts your hardware can make per second.
* You need to know the difficulty (above) and your khash/sec rate (reported by the client).
** [[Mining Hardware Comparison]] has some stats that may help you predict what you could get.
* Visit a calculator or perform the maths yourself,
** http://www.alloscomp.com/bitcoin/calculator.php
** http://www.vnbitcoin.org/bitcoincalculator.php
** https://bitknock.com/calculator
* Remember it's just probability! There are no guarantees you will win every N days.

==Related Links==

* [https://docs.google.com/spreadsheet/ccc?key=0AiFMBvXvL2dtdEZkR2J4eU5rS3B4ei1iUmJxSWNlQ0E Bitcoin Difficulty History]
* [https://www.bitcoinmining.com/what-is-bitcoin-mining-difficulty/ What is Bitcoin Mining Difficulty?]
* See also: [[target]]

[[Category:Technical]]
[[Category:Vocabulary]]

[[pl:Trudność]]

Hashcash

2015-07-13T18:53:50Z

Sunnankar: /* History */

This page explains hashcash and how bitcoin uses it.

==Hashcash==

Bitcoin uses the [http://en.wikipedia.org/wiki/Hashcash hashcash] [[Proof_of_work]] function as the mining core. All bitcoin miners whether CPU, GPU, FPGA or ASICs are expending their effort creating hashcash proofs-of-work which act as a vote in the blockchain evolution and validate the blockchain transaction log.

Like many cryptographic algorithms hashcash uses a hash function as a building block, in the same way that HMAC, or RSA signatures are defined on a pluggable hash-function (commonly denoted by the naming convention of algorithm-hash: HMAC-SHA1, HMAC-MD5, HMAC-SHA256, RSA-SHA1, etc), hashcash can be instantiated with different functions, hashcash-SHA1 (original), hashcash-SHA256^2 (bitcoin), hashcash-Scrypt(iter=1) (litecoin).

===History===

The [https://www.bitcoinmining.com/what-is-hashcash/ hashcash] [https://www.bitcoinmining.com/what-is-proof-of-work/ proof-of-work] function was invented in 1997 by [http://en.wikipedia.org/wiki/Adam_Back Adam Back], and proposed for anti-DoS uses including preventing: anonymous remailer and mail2news gateway abuse, nym name squatting on nymservers (replyable pseudonymous remailer severs), as well as general email anti-spam and general network abuse throttling. Before bitcoin, hashcash was used by SpamAssasin, and (with an incompatible format) by Microsoft (with the name "email postmark") in hotmail, exchange, outlook etc and by i2p anonymity network, mixmaster anonymous remailer components and other systems. Hashcash was also used by [http://en.wikipedia.org/wiki/Hal_Finney_(cypherpunk) Hal Finney]'s bitcoin precursor RPOW as a way to mine coins. Wei Dai's [[B-money Proposal]], and Nick Szabo's similar [[Bit_Gold_proposal]] bitcoin precursors, also were proposed in the context of hashcash mining.

===Hash function choices===

In the original 1997 algorithm hashcash used SHA1 because at that time, this was the defacto and NIST recommended hash, and the previous defacto hash MD5 had recently started to show signs of weakness. Bitcoin being specified/released in 2008/2009 uses SHA256. There is actually no strong reason SHA1 would not have worked also, hashcash relies only on the hash partial preimage resistance property (security up to hash-size, 160-bit with SHA1) and not birthday collision hardness (security up to 80-bit), so the SHA1 hash is big enough. Bitcoin is anyway built to 128-bit security because 256-bit ECDSA is used, which also offers 128-bit security. Never the less SHA256 is the correct and more conservative choice because even SHA1 has started to show some weakenesses, though only in birthday collision, not in 2nd-preimage.

===Double Hash===

Bitcoin is using two hash iterations (denoted SHA256^2 ie "SHA256 function squared") and the reason for this relates to a partial attack on the smaller but related SHA1 hash. SHA1's resistance to birthday attacks has been partially broken as of 2005 in O(2^64) vs the design O(2^80). While hashcash relies on pre-image resistance and so is not vulnerable to birthday attacks, a generic method of hardening SHA1 against the birthday collision attack is to iterate it twice. A comparable attack on SHA256 does not exist so far, however as the design of SHA256 is similar to SHA1 it is probably defensive for applications to use double SHA256. And this is what bitcoin does, it is not necessary given hashcash reliance on preimage security, but it is a defensive step against future cryptanalytic developments. The attack on SHA1 and in principle other hashes of similar design like SHA256, was also the motivation for the NIST SHA3 design competition which is still ongoing.

===Future Hash===

Once the NIST SHA3 contest has finalised, bitcoin might in the future consider adopting hashcash-SHA3 as a security upgrade (eg a single invocation of SHA3 vs a double invocation of SHA256). It seems clear from the SHA1 break, and SHA256 is a similar design, that there was previously a misunderstanding about the security of hash functions against birthday collisions, and SHA3 finalists all aim to fix that issue. One aspect of relevance for hashcash-SHA3 is that there is some debate within the NIST comments process on the proposal of weakening SHA3's resistance to pre-image attacks down to 128-bit (vs the full hash size as with previous hashes). The motivation is a small performance gain, with the rationale that some hash-pluggable algorithms do not rely on full-length pre-image resistance. The proposal has met with significant negative feedback due to it creating a non-standard security assumption (compared to all previous hashes), and therefore it creates risk and all hash-pluggable algorithms (like HMAC, RSA, DSA, hashcash etc) would need to be re-examined on a case by case basis to see if SHA3 is safe to use with them; from the balance of the feedback it seems probable that NIST will accept the feedback and SHA3 will retain the full 256-bit pre-image resistance.

===Cryptanalytic Risks===

A practical issue with switching to hashcash-SHA3 is that it would invalidate all existing ASIC mining hardware, and so is a change that would unlikely to be made except in the face of security risk; there is no indication that SHA1 or SHA256, or SHA256^2 are vulnerable to pre-image attack so the motivation is missing absent new cryptanalytic developments. In addition even if SHA256^2 became easier due to cryptanalytic attack, and miners started using whatever the new algorithmic approach was, it does not necessarily matter as difficulty would just adapt to it. One likely side-effect however would be that it would introduce more memory or pre-computation tradeoffs which could make ASICs unprofitable, or give advantages to people with large resources to do the pre-computations. Pre-computation advantages would perhaps be enough motivation to replace the hash with SHA3. Anyway this is all speculation if and until any pre-image affecting cryptanalytic attacks are found on SHA256.

==Hashcash function==

The hashcash algorithm is relatively simple to understand. The idea builds on a security property of cryptographic hashes, that they are designed to be hard to invert (so-called one-way or pre-image resistant property). You can compute y from x cheaply y=H(x) but it's very hard to find x given only y. A full hash inversion has a known computationally infeasible brute-force running time, being O(2^k) where k is the hash size eg SHA256, k=256, and if a pre-image was found anyone could very efficiently verify it by computing one hash, so there is a huge asymmetry in full pre-image mining (computationally infeasible) vs verification (a single hash invocation).

A second hash pre-image means given one-preimage x of hash y where y=H(x), the task is to find another pre-image of hash y: x' so that y=H(x'). This is not to be confused with a birthday collision which is to find two values x, x' so that H(x)=H(x'), this can be done in much lower work O(sqrt(2^k))=O(2^(k/2)) because you can proceed by computing many H(x) values and storing them until you find a matching pair. It takes a lot of memory, but there are memory-time tradeoffs.

Version 0 of hashcash protocol (1997) used a partial 2nd pre-image, however the later version 1 (2002) uses partial pre-images of a fairly chosen string, rather than digits of pi or something arbitrary, 0^k (ie all 0 string) is used for convenience, so the work is to find x such that H(x)=0. This is also equally fair and only requires one hash invocation to verify vs two with 2nd partial-pre-images. (This optimisation was proposed by Hal Finney & independently by Thomas Boschloo). To make the work easier the definition of a partial-pre-image is to find x such that H(x)/2^(n-k) = 0 where / is the integer quotient from division, n is the size of the hash output (n=256-bits for SHA256) and k is the work factor, ie, the first k bits of the hash output are 0 . So for example k=20 requires average 1 million tries. It is actually the output that partially matches, not the pre-image, so could perhaps more accurately called a pre-image with a partial output match, however partial pre-image effectively a short-hand for that.

===Adding purpose===

If the partial-pre-image x from y=H(x) is random it is just a disconnected proof-of-work to no purpose, everyone can see you did do the work, but they don't know why, so users could reuse the same work for different services. To make the proof-of-work be bound to a service, or purpose, the hash must include s, a service string so the work becomes to find H(s,c)/2^(n-k)=0. The miner varies counter c until this is true. The service string could be a web server domain name, a recipients email address, or in bitcoin a block of the bitcoin blockchain ledger.

One additional problem is that if multiple people are mining, using the same service string, they must not start with the same x or they may end up with the same proof, and anyone looking at it will not honor a duplicated copy of the same work as it could have been copied without work, the first to present it will be rewarded, and others will find their work rejected. To avoid risking wasting work in this way, there needs to be a random starting point, and so the work becomes to find H(s,x,c)/2^(n-k) = 0 where x is random (eg 128-bits to make it statistically infeasible for two users to maliciously or accidentally start at the same point), and c is the counter being varied, and s is the service string.

This is what hashcash version 1 and bitcoin does. In fact in bitcoin the service string is the coinbase and the coinbase includes the recipients reward address, as well as the transactions to validate in the block. Bitcoin actually does not include a random start point x, reusing the reward address as the randomization factor to avoid collisions for this random start point purpose, which saves 16-bytes of space in the coinbase. For privacy bitcoin expect the miner to use a different reward address on each successful block.

===More Precise Work===

Hashcash as originally proposed has work 2^k where k is an integer, this means difficulty can only be scaled in powers of 2, this is slightly simpler as you can see and fully measure the difficulty just by counting 0s in hex/binary and was adequate for prior uses. (A lot of hashcash design choices are motivated by simplicity).

But because bitcoin needs more precise and dynamic control of work (to target 10-minute block interval accurately), it changes k to be a fractional (floating-point) so the work becomes to find H(s,x,c) < 2^(n-k) which is equivalent if k is an integer. Bitcoin defines target = 2^(n-k), so the work can be more simply written to find H(s,x,c) < target. Of course because of luck the block time actually has quite high variance, but the average is still more accurately targeted by the introduction of fractional k.

===Work, difficulty & cryptographic security===

Hashcash expresses security margin in the standard cryptographic security terms O(2^k) where for comparison DES offers k=56-bits of security, ECDSA-256 offers k=128-bits of security, and because its widely used this log2 way of expressing work and security can also be useful for making security comparisons.

Bitcoin rate of work is called the [https://blockchain.info/q/hashrate network hashrate] in GH/sec. As the target block interval is 10 minutes that can be converted to cryptographic security as log2(hashrate*600), so that of Nov 2013 hashrate is 4 petahash/sec and bitcoin's hashcash-256^2 proofs-of-works are 62-bits (including +1 for double hash).

Bitcoin also defines a new notion of (relative) difficulty which is the work required so that at current network hashrate a block is expected to be found every 10 minutes. It is expressed relative to a minimum work unit of 2^32 iterations (approximately, technically minimum work is 0xFFFF0000 due to bitcoin implementation level details). Bitcoin difficulty is simple to approximately convert to log2 cryptographic security: k=log2(difficulty)+32 (or for high accuracy log2(difficulty*0xFFFF0000)). Difficulty is related to the target simply as difficulty = target / 0xFFFF0000.

It is perhaps easier to deal with high difficulties in log2 scale (a petahash/second is a 16 decimal digit number of hashes per second), and makes them comparable to other cryptographic security statements. For example the EFF "deepcrack" [https://en.wikipedia.org/wiki/EFF_DES_cracker DES cracker] project built a hardware brute force machine capable of breaking a DES key in 56 hours to make a political point that 56-bit DES was too weak in 1998 at a cost of $250,000 (plus volunteer design time). By comparison bitcoin network does 62-bits (including +1 for double hash) every 10-minutes and is 537,000 times more powerful than deepcrack, or could if it were focused on DES rather than SHA256 crack a DES key in 9 seconds to deepcracks 56 hours.

===Miner privacy===

In principle a miner should therefore for privacy use a different reward-address for each block (and reset the counter to 0). Why Satoshi's early mined bitcoins were potentially linked, was because while he changed the reward-addresss, he forgot to reset the counter after each successful mine, which is a bitcoin mining privacy bug. In fact with bitcoin the counter also should be obscured otherwise you would reveal your effort level, and if you have a lot of mining power that may imply who the coin belongs to. Bitcoin does this via the nonce and extra-nonce. Nonce starts at 0, but extra nonce is random. Together these form a randomized counter hiding the amount of effort that went into the proof, so no one can tell if it was a powerful but unlucky miner who worked hard, or a weak miner who was very lucky.

Additionally with the introduction of mining pools, if the miner uses the same reward address for all users, which is what the current mining protocols do, then there is risk that users may redo work. To avoid users redoing work, miners hand out defined work for the users to do. However this creates an unnecessary communication round trip and in early protocol versions perhaps was a factor in the decision to have the pool send the actual block to mine, which means the miners are not validating their own blocks, which delegates validation authority, though not work, to the pool operator, reducing the security of the bitcoin network. The more recent mining protocol version allows the user to add their own block definition, but still unnecessarily incur round trips for handing out work allocation. Because the new pooled-mining protocol has a miner chosen extraNonce this acts as a random start factor so there is actually no need to talk to the pool for work allocation, a pool could have a static published address, and miners could just do work of whatever size they chose, and submit it to the pool as a UDP packet. (If privacy is required by the miner, it could use the public derivation method from BIP 32 to allow the node to tell the miner via an encrypted message with the mining work, which factor to multiply the static public key by.)

===Scrypt proof-of-work===

It is a misunderstanding to talk about the Scrypt proof-of-work.
Scrypt is not intended as a proof-of-work function, but a stretched key-derivation function, and while it is by design expensive to compute with high iterations, it can not be used to make an efficiently publicly auditable proof-of-work, as verifying costs the same as creating.

Hashcash with the internal hash function of Scrypt may be denoted hashcash-Scrypt(1). Scrypt, by Colin Percival, is a key-derivation function for converting user chosen passphrases into keys. It is salted (to prevent pre-computation/rainbow table attacks), and the hash is iterated many times to slow down passphrase grinding. Scrypt is similar in purpose to the defacto standard passphrase key-derivation function PBKDF2 (which uses HMAC-SHA1 internally). The differentiator and why people might choose Scrypt rather than PBDF2 is that Scrypt's inner hash uses more memory so the GPU (or theoretical Scrypt ASIC/FPGA) advantage in password grinding is reduced compared to CPUs.

This does not use the key-stretching feature of Scrypt so mining is not actually using Scrypt directly, but only the inner Scrypt hash (accessed by setting the iteration parameter to one iteration). So Scrypt's key-stretching function is not being used at all to contribute to the hardness, unlike its normal use for key protection eg in deriving the encryption key from user passphrase to encrypt bitcoin wallets. The reason Scrypt's key-stretching can not be used for mining is because that simultaneously makes it more expensive to verify by the same factor. This hashcash variant can be denoted hashcash-Scrypt(iter=1,mem=128KB) or shortened to hashcash-Scrypt(1). The other major scrypt parameter denotes the amount of memory used (usually 128kB).

===Decentralization: hashcash-Scrypt vs hashcash-SHA256===

The 128kB Scrypt memory footprint makes litecoin arguably less vulnerable to centralization of mining power arising from limited access to or ownership of ASIC equipment by users. It's arguable and unclear, because there are counter arguments: that hashcash-SHA256^2 is very simple, so a skilled individual with his personal savings or a small Kickstarter project could design and put in an order with a chip-fabricator. This simplicity ensures that many people will do it and ASICs should become available. Conversely it is somewhat more difficult in comparison to make an hashcash-Scrypt(1) ASIC so perhaps litecoin will prove in the mid-term actually worse for centralization, if a well funded commercial entity corners the market by having faster, but proprietary, not available on the market, hashcash-Scrypt(1) ASICs that render litecoin GPU mining unprofitable.

Note also a mitigating factor is that it is considered that hashcash-Scrypt(1) should offer less speed up from ASIC implementation vs GPUs than hashcash-SHA256^2. This is claimed because of the argument that the die area taken up by 128kB of RAM, which it might be thought must be dedicated to each Scrypt(1) core, would reduce the number of Scrypt(1) cores that fit per chip. Note however that Scrypt(1) is not actually securely memory-hard in that it makes no attempt to prevent time-memory tradeoffs, so it is actually possible to repeat the computation of internal rounds to reduce the memory requirement. In theory therefore it would be possible though more computation expensive to implement Scrypt(iter=1, mem=128kB) with minimal memory, just with more work. In hardware the time-memory tradeoff would be optimized to find the optimal amount of memory to use, and it is quite possible the optimal amount would be less than 128kB.

Hashcash-Scrypt(1) also has a disadvantage relative to hashcash-SHA256^2 in that it is significantly slower to verify, as the verification cost of one iteration of Scrypt(mem=128kB) is far higher than a two SHA256 hashes. This makes validating the litecoin blockchain more CPU and memory intensive for all full nodes. Note however that the dominating CPU work of validation is the verification of the per transaction ECDSA signatures of the multiple transactions in a block. Even one ECDSA signature is slower than one Scrypt(1) verification which is done once per block, and there are many transactions (and so ECDSA signature verifications) to verify within a block.

Comparison of mining pools

2015-07-07T15:46:36Z

Sunnankar: /* See also */

Reward types & explanation:
* '''CPPSRB''' - Capped Pay Per Share with Recent Backpay. [http://eligius.st/wiki/index.php/Capped_PPS_with_Recent_Backpay]
* '''DGM''' - Double Geometric Method. A hybrid between PPLNS and Geometric reward types that enables to operator to absorb some of the variance risk. Operator receives portion of payout on short rounds and returns it on longer rounds to normalize payments. [https://bitcointalk.org/index.php?topic=39497.0]
* '''ESMPPS''' - Equalized Shared Maximum Pay Per Share. Like SMPPS, but equalizes payments fairly among all those who are owed. [http://forum.bitcoin.org/index.php?topic=12181.msg378851#msg378851]
* '''POT''' - Pay On Target. A high variance PPS variant that pays on the difficulty of work returned to pool rather than the difficulty of work served by pool [https://bitcointalk.org/index.php?topic=131376.0]
* '''PPLNS''' - Pay Per Last N Shares. Similar to proportional, but instead of looking at the number of shares in the round, instead looks at the last N shares, regardless of round boundaries.
* '''PPLNSG''' - Pay Per Last N Groups (or shifts). Similar to PPLNS, but shares are grouped into "shifts" which are paid as a whole.
* '''PPS''' - Pay Per Share. Each submitted share is worth certain amoutripnt of BC. Since finding a block requires <current difficulty> shares ''on average'', a PPS method with 0% fee would be 25 BTC divided by <current difficulty>. It is risky for pool operators, hence the fee is highest.
* '''Prop.''' - Proportional. When block is found, the reward is distributed among all workers proportionally to how much shares each of them has found.
* '''RSMPPS''' - Recent Shared Maximum Pay Per Share. Like SMPPS, but system aims to prioritize the most recent miners first. [http://eligius.st/wiki/index.php/Shared_Maximum_PPS]
* '''Score''' - Score based system: a proportional reward, but weighed by time submitted. Each submitted share is worth more in the function of time ''t'' since start of current round. For each share score is updated by: score += exp(t/C). This makes later shares worth much more than earlier shares, thus the miner's score quickly diminishes when they stop mining on the pool. Rewards are calculated proportionally to scores (and not to shares). (at slush's pool C=300 seconds, and every hour scores are normalized)
* '''SMPPS''' - Shared Maximum Pay Per Share. Like Pay Per Share, but never pays more than the pool earns. [http://eligius.st/wiki/index.php/Shared_Maximum_PPS]
[http://eligius.st/~luke-jr/samples/800MH-3/ Visual examples of the various payout methods]

{| class="wikitable sortable" border="1"
|-
! Name !! Location !! TH/s<ref name="hashrate2"/>
! Merged Mining<ref name="merged"/>
! Reward Type !! Transaction fees!!PPS Fee!!Other Fee!! [[File:Gwk.png|link=Getwork]] !! [[File:Stm.png|link=Stratum_mining_protocol]] !! [[getblocktemplate|GBT]]
! Launched !! Variance !! Forum !! Website
|-
| [[BitcoinAffiliateNetwork]] || {{flag|us|}}{{flag|eu}}{{flag|cn|}}{{flag|nl|}}{{flag|au|}} || 2000 || [[NMC]], [[DOGE]] || PPS || {{PoolFees}} || 0% || 0% || {{No}} || {{Yes}} ||
| 2014-07-15 || User/Dynamic || [https://bitcointalk.org/index.php?topic=722202.0 link] || [http://mining.bitcoinaffiliatenetwork.com/ link]
|-
| [[Bitcoin Pooled Mining|Slush's pool (mining.bitcoin.cz)]]
| Global || 12000 || No || Score || {{SharedFees}} || || 2% || || {{Yes}} ||
| 2010-11-27 || User<ref name="changeable"/> || [http://bitcointalk.org/?topic=1976 link] || [http://mining.bitcoin.cz/ link]
|-
| [[BitMinter]] || {{flag|us}}{{flag|de}} || 2700 || [[NMC]] || PPLNSG || {{SharedFees}} || || 1% || {{Yes}} || {{Yes}} || {{Yes}}
| 2011-06-26 || User<ref name="changeable"/>/Dynamic || [http://bitcointalk.org/?topic=27062 link] || [https://bitminter.com link]
|-
| [[BTC Guild]] || {{flag|us}}{{flag|eu}} || 10500 || [[NMC]]
| PPLNSG || {{SharedFees}} || || 2% || {{Yes}} || {{Yes}} || {{No}}
| 2011-05-09 || User<ref name="changeable"/>/Dynamic
| [http://bitcointalk.org/?topic=49417 link] || [https://www.btcguild.com/ link]
|-
| [[BTCMine]] || {{flag|us|label=1}} || 0.1 || No || Score || {{PoolFees}} || || 0% || {{Yes}} || ||
| 2011-03-11 || Diff 1 || [http://bitcointalk.org/?topic=4251 link] || [http://btcmine.com/ link]
|-
| [[BTCDig]] || {{flag|us|label=1}}|| 7 || No || DGM || {{PoolFees}} || || 0% || || {{Yes}} ||
| 2013-07-04 || User<ref name="changeable"/>/Dynamic 20SPM || [https://bitcointalk.org/index.php?topic=249627 link] || [http://btcdig.com/ link]
|-
| [[btcmp.com]] || {{flag|de|label=1}}|| 1.4 || No || PPS || {{PoolFees}} || 4% || || {{Yes}} || ||
| 2011-06-28 || Diff 1 || || [http://www.btcmp.com/ link]
|-
| [[CKPool]] || {{flag|us|label=1}} || 3500 || No || PPLNS || {{SharedFees}} || || 0.9% || {{No}} || {{Yes}} || {{No}}
| 2014-09-20 || User<ref name="changeable"/>/Dynamic 18SPM || [https://bitcointalk.org/index.php?topic=789369.0 link] || [http://www.kano.is link]
|-
| [[Eclipse Mining Consortium]]
| Global || 246 || No || DGM/PPS || {{PoolFees}} || 5% || 0% || {{Yes}} || {{Yes}} || {{Yes}}
| 2011-06-14 || User<ref name="changeable"/>/Dynamic
| [http://bitcointalk.org/?topic=16385 link] || [https://eclipsemc.com link]
|-
| [[Eligius]] || {{flag|us|label=1}}|| 4000 || [[NMC]] 105% PPS<ref name="eligiusnmc"/> || CPPSRB || {{SharedFees}} || 0% || || {{Yes}} || {{Yes}} || {{Yes}}
| 2011-04-27 || Dynamic: 32 shares/m || [http://bitcointalk.org/?topic=23768 link] || [http://eligius.st link]
|-
| [[GHash.IO]] || {{flag|nl|label=1}}|| 60000 || [[NMC]], IXC, [[Devcoin]] || PPLNS || {{SharedFees}} || 0% || 0% || {{No}} || {{Yes}} || {{No}}
| 2013-07-01 || User<ref name="changeable"/> || [https://support.cex.io link] || [https://ghash.io/ link]
|-
| [[Give Me COINS]] || {{flag|us}}{{flag|eu}} || 1000 || [[NMC]] || PPLNS || {{SharedFees}} || || 0%|| {{No}} || {{Yes}} || {{Yes}}
| 2013-08-12 || Dynamic || [https://bitcointalk.org/index.php?topic=272017.0 link] || [http://give-me-coins.com link]
|-
| [[Merge Mining Pool]] || {{flag|us|label=1}}|| 50 || [[NMC]], IXC, [[Devcoin]]
| DGM || {{SharedFees}} || || 1.5% || {{No}} || {{Yes}} || {{No}}
| 2012-01-08 || User<ref name="changeable"/> || [http://bitcointalk.org/?topic=57148 link] || [http://mmpool.org link]
|-
| [[MinerGate]] || {{flag|eu|label=1}}|| || Yes || PPS, PPLNS || {{PoolFees}} || 2.5% || 2% || {{Yes}} || {{Yes}} || {{No}}
| 2014-03-24 || Dynamic || [https://bitcointalk.org/index.php?topic=528848.0 link] || [http://minergate.com/ link]
|-
| [[Multipool]] || {{flag|us}}{{flag|eu}} || 400 || [[NMC]], IXC, [[Devcoin]] || Prop. || {{SharedFees}} || || 0% || {{Yes}} || {{Yes}} || {{No}}
| 2012-03-15 || User || [https://bitcointalk.org/index.php?topic=311067.0 link] || [https://www.multipool.us/ link]
|-
| [[Ozco.in]] || {{flag|us}}{{flag|eu}}{{flag|au}}{{flag|cn}} || 4 || No || DGM || {{SharedFees}} || || 1% || {{No}} || {{Yes}} || {{No}}
| 2011-06-07 || User<ref name="changeable"/>/Dynamic
| [http://bitcointalk.org/?topic=14085 link] || [https://ozco.in link]
|-
| [[P2Pool]] || Global (p2p) || 800 || Solo<ref name="solomm"/> || PPLNS || {{SharedFees}} || || 0% || {{No}}<ref name="local"/> || {{Yes}} || {{No}}
| 2011-06-17 || User<ref name="changeable"/> || [http://bitcointalk.org/?topic=18313 link] ||
|-
| [[PolMine]] || {{flag|pl|label=1}}|| 700 || [[NMC]] || SMPPS || {{SharedFees}} || 1% || 0% || {{Yes}} || {{Yes}} || {{Yes}}
| 2011-06-13 || Dynamic/User || [http://forum.polmine.pl/ link] || [https://polmine.pl/?setlang=en link]
|-
|}

== SPV Mining / Old Bitcoin Core ==

The following pools are known or strongly suspected to be mining on top of blocks before fully validating them with Bitcoin Core 0.9.5 or later. Miners doing this have already lost over $50,000 USD during the 4 July 2015 fork and have created a situation where small numbers of confirmations are much less useful than they normally are.

* BTC Nuggets
* [https://www.f2pool.com/ F2Pool]<ref name="spv_despite_incident">[https://bitcointalk.org/index.php?topic=700411.msg11790734#msg11790734 Intention to continue SPV mining], Wang Chun, 4 July 2015</ref>
* AntPool<ref name="spv_despite_incident" />

The following pools are believed to be currently fully validating blocks with Bitcoin Core 0.9.5 or later (0.10.2 or later recommended due to DoS vulnerabilities):

* [[BitMinter]]
* BTC China (described as SPV mining<ref name="spv_despite_incident" />, but they're performing effective valiation)
* [[CKPool]]
* [[Eligius]]
* [[P2Pool]]

== References ==

<references>

<ref name="hashrate2">Note that pool hashrate is largely irrelevant but can be seen as a popularity measurement. Note however that it is a theoretical security issue if one pool gains above 50% of the total computational power of the network, thus consider joining a pool based on other metrics.</ref>

<ref name="merged">Merged mining allows miners to mine on multiple [[block chains]] at the same time with the same hashing.</ref>

<ref name="local">Miner-operated proxy available.</ref>
<ref name="changeable">The difficulty of the shares can be changed by the user.</ref>
<ref name="solomm">Merged mining can be done on a "solo mining" basis (payouts in the merged chain are not pooled).</ref>

<ref name="eligiusnmc">As of March 8, 2014, payouts have been labelled as broken by the pool operator. There is no current ETA to a fix.</ref>
</references>

== See also ==
* [[Pooled mining]]
* [http://blockorigin.pfoe.be/chart.php Hashrate distribution pie chart]
* [https://www.bitcoinmining.com/ Bitcoin Mining]
* [https://www.youtube.com/watch?v=GmOzih6I1zs Video: What is Bitcoin Mining]
* [https://www.bitcoinmining.com/bitcoin-mining-pools/ Bitcoin Mining Pools]

[[Category:Mining]]
{{Pools}}

Bitcoin

2015-07-07T15:35:02Z

Sunnankar: /* See Also */

'''Bitcoin''' is a decentralized [[digital currency]] created by developer [[Satoshi Nakamoto]]. It does not rely on a central server to process transactions or store funds. There are a maximum of 2,099,999,997,690,000 Bitcoin elements (called satoshis), which are currently most commonly measured in units of 100,000,000 known as BTC. Stated another way, no more than 21 million BTC can ever be created.

{{As of|April 2014}}, it is the most widely used alternative currency,<ref name="Quantitative Analysis of the Full Bitcoin Transaction Graph">{{cite web|title=Quantitative Analysis of the Full Bitcoin Transaction Graph|url=http://eprint.iacr.org/2012/584.pdf|publisher=Cryptology ePrint Archive|accessdate=18 October 2012|author=Ron Dorit|coauthors=Adi Shamir|page=17|quote=The Bitcoin system is the best known and most widely used alternative payment scheme,...}}</ref><ref name="Mt.Gox data">{{Cite web|title=Mt.Gox data|url=http://bitcoincharts.com/markets/mtgoxUSD.html|publisher=Bitcoincharts}}</ref> now with the total market cap over 6 billion US dollars<ref>{{cite web|title=Market Capitalization|url=https://blockchain.info/charts/market-cap|publisher= [[BlockChain.info]] |accessdate=21 April 2014}}</ref>.

Bitcoin has no central issuer; instead, the peer-to-peer network regulates Bitcoins, transactions and issuance according to consensus in network software.
Bitcoins are issued to various nodes that verify transactions through computing power;
it is established that there will be a limited and scheduled release of no more than 21 million BTC worth of coins, which will be fully issued by the year 2140.

Internationally, Bitcoins can be exchanged and managed through various websites and [[software]] along with physical banknotes and coins.<ref>{{Cite web|title=Physical Bitcoins by Casascius|url=https://www.casascius.com/|publisher=Casascius Coins|accessdate=29 September 2012}}</ref><ref>{{Cite web|title=Bitbills|url=http://www.bitbills.com/|publisher=Bitbills|accessdate=29 September 2012}}</ref>

==History==
{{main|History}}

A cryptographic system for untraceable payments was first described by David Chaum in 1982.<ref>[http://blog.koehntopp.de/uploads/Chaum.BlindSigForPayment.1982.PDF David Chaum, Blind signatures for untraceable payments], Advances in Cryptology - Crypto '82, Springer-Verlag (1983), 199–203.</ref> In 1990 Chaum extended this system to create the first cryptographic anonymous electronic cash system.,<ref>{{cite journal|journal=Lecture Notes in Computer Science|last1=Chaum|first1=David|last2=Fiat|first2=Amos|last3=Naor|first3=Moni|title=Untraceable Electronic Cash|url=http://blog.koehntopp.de/uploads/chaum_fiat_naor_ecash.pdf}}</ref> which became known as ecash.
<ref>{{cite web|url=http://www.wired.com/wired/archive/2.12/emoney.html|publisher=Wired|title=E-Money (That's What I Want)|date=1994–2012|author=Steven Levy}}</ref> In 1998 Wei Dai published a description of an anonymous, distributed electronic cash system which he called "b-money".<ref>{{cite web|title=B-Money|url=http://www.weidai.com/bmoney.txt|author=Wei Dai|year=1998}}</ref> Around the same time, Nick Szabo created ''bit gold''.<ref>{{cite web|url=http://spectrum.ieee.org/computing/software/bitcoin-the-cryptoanarchists-answer-to-cash/0|title=Bitcoin: The Cryptoanarchists’ Answer to Cash|publisher=IEEE Spectrum|quote=Around the same time, Nick Szabo, a computer scientist who now blogs about law and the history of money, was one of the first to imagine a new digital currency from the ground up. Although many consider his scheme, which he calls “bit gold,” to be a precursor to Bitcoin}}</ref><ref name="bitgold">{{cite web|title=Bit gold|url=http://unenumerated.blogspot.co.uk/2005/12/bit-gold.html|author=Nick Szabo|quote=My proposal for bit gold is based on computing a string of bits from a string of challenge bits, using functions called variously "client puzzle function," "proof of work function," or "secure benchmark function.". The resulting string of bits is the proof of work.... The last-created string of bit gold provides the challenge bits for the next-created string.}}</ref> Like Bitcoin, ''Bit gold'' was a currency system where users would compete to solve a [[proof of work]] function, with solutions being cryptographically chained together and published via a distributed property title registry. A variant of ''Bit gold'', called ''Reusable Proofs of Work'', was implemented by Hal Finney.<ref name="bitgold"/>

In 2008, Satoshi Nakamoto published a [[Bitcoin_white_paper|paper]]<ref name="whitepaper">{{cite web
|last= Nakamoto
|first= Satoshi
|title= Bitcoin: A Peer-to-Peer Electronic Cash System
|url= http://www.cs.kent.edu/~JAVED/class-P2P12F/papers-2012/PAPER2012-p2p-bitcoin-satoshinakamoto.pdf
|accessdate = 14 December 2010
|date= 24 May 2009
|postscript=
}}</ref><ref>{{cite web
|url= http://article.gmane.org/gmane.comp.encryption.general/12588/
|title= Bitcoin P2P e-cash paper
}}</ref> on The Cryptography Mailing list at metzdowd.com<ref>[http://www.mail-archive.com/search?l=cryptography@metzdowd.com&q=from:%22Satoshi+Nakamoto%22 Satoshi's posts to Cryptography mailing list]</ref> describing the Bitcoin protocol.

The Bitcoin network came into existence on 3 January 2009 with the release of the first Bitcoin client, [[wxBitcoin]], and the issuance of the first Bitcoins.<ref>{{cite web |title=Block 0 – Bitcoin Block Explorer |url=http://blockexplorer.com/block/000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f }}</ref><ref>{{cite web |url=http://www.mail-archive.com/cryptography@metzdowd.com/msg10142.html |title=Bitcoin v0.1 released}}</ref><ref>{{cite web |url=http://sourceforge.net/news/?group_id=244765 |title=SourceForge.net: Bitcoin}}</ref>
A year after, the initial exchange rates for Bitcoin were set by individuals on the bitcointalk forums.{{Citation needed|date=October 2012}} The most significant transaction involved a 10,000 BTC pizza.<ref>{{cite web|title=The Rise and Fall of Bitcoin|url=http://www.wired.com/magazine/2011/11/mf_bitcoin/|publisher=Wired|accessdate=13 October 2012}}</ref>
Today, the majority of Bitcoin exchanges occur on the [[Bitstamp]] Bitcoin exchange.<ref>{{cite web | title = Exchange volume distribution | work = by market | publisher = [[Bitcoin Charts]] | date = April 15, 2014 | url = http://bitcoincharts.com/charts/volumepie/ | accessdate = 2014-04-15 }}</ref>

In 2011, Wikileaks,<ref>{{cite news
|last= Greenberg
|first= Andy
|url= http://blogs.forbes.com/andygreenberg/2011/06/14/wikileaks-asks-for-anonymous-bitcoin-donations/
|title= WikiLeaks Asks For Anonymous Bitcoin Donations – Andy Greenberg – The Firewall – Forbes
|publisher= Blogs.forbes.com
|date= 2011-06-14
|accessdate = 2011-06-22
}}</ref> [[Freenet]],<ref>{{cite web
|url= https://freenetproject.org/donate.html
|title= /donate
|publisher= The Freenet Project
|date=
|accessdate = 2011-06-22
}}</ref> Singularity Institute,<ref>[http://singinst.org/donate/ SIAI donation page]</ref> Internet Archive,<ref>[http://www.archive.org/donate/index.php Internet Archive donation page]</ref> Free Software Foundation<ref>[https://my.fsf.org/donate/other/ Other ways to donate]</ref> and others, began to accept donations in Bitcoin. The Electronic Frontier Foundation did so for a while but has since stopped, citing concerns about a lack of legal precedent about new currency systems, and because they "generally don't endorse any type of product or service."<ref>{{cite web
|url= https://www.eff.org/deeplinks/2011/06/eff-and-bitcoin
|title= EFF and Bitcoin | Electronic Frontier Foundation
|publisher= Eff.org
|date= 2011-06-14
|accessdate = 2011-06-22
}}</ref> Some small businesses had started to adopt Bitcoin. LaCie, a public company, accepts Bitcoin for its Wuala service.<ref>{{Cite web|url=http://www.wuala.com/en/bitcoin |title=Secure Online Storage – Backup. Sync. Share. Access Everywhere |publisher=Wuala |date= |accessdate = 2012-01-24}}</ref>

In 2012, BitPay reports of having over 1000 merchants accepting Bitcoin under its payment processing service.<ref>{{cite web|title=BitPay Signs 1,000 Merchants to Accept Bitcoin Payments|url=http://www.americanbanker.com/issues/177_176/bitpay-signs-1000-merchants-to-accept-bitcoin-payments-1052538-1.html|publisher=American Banker|accessdate=12 October 2012}}</ref>

==Administration==
Bitcoin is administered through a decentralized peer-to-peer network.<ref name="whitepaper"/> Cryptographic technologies and the peer-to-peer network of computing power enables users to make and verify irreversible, instant online Bitcoin payments, without an obligation to trust and use centralized banking institutions and authorities. Dispute resolution services are not made directly available. Instead it is left to the users to verify and trust the parties they are sending money to through their choice of methods.

Bitcoins are issued according to rules agreed to by the majority of the computing power within the Bitcoin network. The core rules describing the predictable issuance of Bitcoins to its verifying servers, a voluntary and competitive transaction fee system and the hard limit of no more than 21 million BTC issued in total.<ref name="whitepaper"/>

Bitcoin does not require a central bank, State,<ref>{{cite web
|url= http://spectrum.ieee.org/computing/software/bitcoin-the-cryptoanarchists-answer-to-cash/3
|title= Bitcoin: The Cryptoanarchists' Answer to Cash
|publisher= IEEE.org
|date= June 2012
|accessdate = 2012-06-05
}}</ref> or incorporated backers.

==Services==
{{main|Wallet}}

Bitcoins are sent and received through software and websites called wallets. They send and confirm transactions to the network through Bitcoin addresses, the identifiers for users' Bitcoin wallets within the network.<ref name="whitepaper"/>

===Bitcoin addresses===
{{main|Address}}

Payments are made to Bitcoin "addresses": human-readable strings of numbers and letters around 33 characters in length, always beginning with the digit 1 or 3, as in the example of ''31uEbMgunupShBVTewXjtqbBv5MndwfXhb''.

Users obtain new Bitcoin addresses from their Bitcoin software. Creating a new address can be a completely offline process and require no communication with the Bitcoin network.

===Transaction fees===
{{main|Transaction fees}}
Transaction fees may be included with any transfer of Bitcoins. {{As of|2012}} many transactions are processed in a way which makes no charge for the transaction. For transactions which consume or produce many coins (and therefore have a large data size), a small transaction fee is usually expected.

===Confirmations===
{{main|Confirmation}}

The network's software confirms a transaction when it records it in a block. Further blocks of transactions confirm it even further. After six confirmations/blocks, a transaction is confirmed beyond reasonable doubt.

The network must store the whole transaction history inside the blockchain, which grows constantly as new records are added and never removed. Nakamoto conceived that as the database became larger, users would desire applications for Bitcoin that didn't store the entire database on their computer. To enable this, the blockchain uses a [[merkle tree]] to organize the transaction records in such a way that client software can locally delete portions of its own database it knows it will never need, such as earlier transaction records of Bitcoins that have changed ownership multiple times.

==Economics==

===Initial distribution===

Bitcoin has no centralized issuing authority.<ref name="ars-06-08-11">
{{Cite news
|first= Thomas
|last= Lowenthal
|title= Bitcoin: inside the encrypted, peer-to-peer digital currency
|newspaper= Ars Technica
|date= 8 June 2011
|url= http://arstechnica.com/tech-policy/news/2011/06/bitcoin-inside-the-encrypted-peer-to-peer-currency.ars
}}</ref><ref>{{cite news
|author= Sponsored by
|url= http://www.economist.com/blogs/babbage/2011/06/virtual-currency
|title= Virtual currency: Bits and bob
|publisher= The Economist
|date=
|accessdate = 2011-06-22
}}</ref><ref>{{cite web
|last= Geere
|first= Duncan
|url= http://www.wired.co.uk/news/archive/2011-05/16/bitcoin-p2p-currency
|title= Peer-to-peer currency Bitcoin sidesteps financial institutions (Wired UK)
|publisher= Wired.co.uk
|date=
|accessdate = 2011-06-22
}}</ref> The network is programmed to increase the money supply as a geometric series until the total number of Bitcoins reaches 21 million BTC.<ref name="Quantitative Analysis of the Full Bitcoin Transaction Graph"/> {{As of|2012|10}} slightly over 10 million of the total 21 million BTC had been created; the current total number created is available online.<ref>{{cite web
|title= Total Number of Bitcoins in Existence
|url= http://blockexplorer.com/q/totalbc
|work= Bitcoin Block Explorer
|accessdate = 2012-10-03
}}</ref> By 2013 half of the total supply will have been generated, and by 2017, three-quarters will have been generated. To ensure sufficient granularity of the [[money supply]], clients can divide each BTC unit down to eight decimal places (a total of 2.1 × 1015 or 2.1 quadrillion units).<ref name="lwn">{{Cite news
|author= Nathan Willis
|date= 2010-11-10
|title= Bitcoin: Virtual money created by CPU cycles
|publisher= LWN.net
|url= http://lwn.net/Articles/414452/
}}</ref>

The network {{As of|2012|lc=on}} required over one million times more work for confirming a block and receiving an award (25 BTC {{As of|2012|2|lc=on}}) than when the first blocks were confirmed.
The difficulty is automatically adjusted every 2016 blocks based on the time taken to find the previous 2016 blocks such that one block is created roughly every 10 minutes.

Those who chose to put computational and electrical resources toward mining early on had a greater chance at receiving awards for block generations. This served to make available enough processing power to process blocks. Indeed, without miners there are no transactions and the Bitcoin economy comes to a halt.

===Exchange rate===
Prices fluctuate relative to goods and services more than more widely accepted currencies;
the price of a Bitcoin is not static.

In August 2012, 1 BTC traded at around $10.00 USD. Taking into account the total number of Bitcoins mined, the monetary base of the Bitcoin network stands at over 110 million USD.<ref>[http://www.bitcoinwatch.com/ http://www.bitcoinwatch.com/] Bitcoin statistics</ref>

== Anonymity ==
{{main|Anonymity & Security}}

=== Transactions ===

While using bitcoins is an excellent way to make your purchases, donations, and p2p payments, without losing money through inflated transaction fees, transactions are never truly anonymous. Buying Bitcoin you pass identification, Bitcoin transactions are stored publicly and permanently on the network, which means anyone can see the balance and transactions of any Bitcoin address. Bitcoin activities are recorded and available publicly via the [[blockchain]], a comprehensive database which keeps a record of bitcoin transactions.

=== Buying/selling bitcoins ===

All exchanges require the user to scan ID documents, and large transactions must be reported to the proper governmental authority. When you use Bitcoin to pay for goods and services, you will of course need to provide your name and address to the seller for delivery purposes.

This means that a third party with an interest in tracking your activities can use your visible balance and ID information as a basis from which to track your future transactions or to study previous activity. In short, you have compromised your [[security]] and [[privacy]].

In addition to conventional exchanges like Bitstamp, Bitfinex, Kraken and Coinable there are also Peer to peer exchanges like localbitcoins and Paxful. Peer to peer exchanges will often not collect KYC and identity information directly from users, instead they let the users handle KYC amongst themselves. These can often be a better alternative for those looking to purchase bitcoin quickly and without KYC delay.

=== Mixing services ===

[http://anonymity.co.in/mixing_services.html Mixing services] are used to avoid compromising of privacy and security. Mixing services provide to periodically exchange your bitcoins for different ones which cannot be associated with the original owner.

== Security ==
{{seealso|Weaknesses}}

In the history of bitcoin, there have been a few [[incidents]], caused by problematic as well as malicious transactions. In the worst such incident, and the only one of its type, a person was able to pretend that he had a practically infinite supply of bitcoins, for almost 9 hours.

Bitcoin relies, among other things, on [http://en.wikipedia.org/wiki/Public-key_cryptography public key cryptography] and thus may be vulnerable to [http://en.wikipedia.org/wiki/Elliptic_curve_cryptography#Quantum_computing_attacks quantum computing attacks] if and when practical quantum computers can be constructed.

If multiple different software packages, whose usage becomes widespread on the Bitcoin network, disagree on the protocol and the rules for transactions, this could potentially cause a fork in the block chain, with each faction of users being able to accept only their own version of the history of transactions. This could influence the price of bitcoins.

A global, organized campaign against the currency or the software could also influence the demand for bitcoins, and thus the exchange price.

==Bitcoin mining==
{{main|Mining}}

Bitcoin mining nodes are responsible for managing the Bitcoin network.

Bitcoins are awarded to Bitcoin nodes known as "miners" for the solution to a difficult [[proof-of-work]] problem which confirms transactions and prevents double-spending. This incentive, as the Nakamoto white paper describes it, encourages "nodes to support the network, and provides a way to initially distribute coins into circulation, since no central authority issues them."<ref name="whitepaper" />

Nakamoto compared the generation of new coins by expending CPU time and electricity to gold miners expending resources to add gold to circulation.<ref name="whitepaper"/>

===Node operation===

The node software for the Bitcoin network is based on peer-to-peer networking, digital signatures and cryptographic proof to make and verify transactions. Nodes broadcast transactions to the network, which records them in a public record of all transactions, called the ''blockchain'', after validating them with a [[proof-of-work|proof-of-work system]].

Satoshi Nakamoto designed the first Bitcoin node and mining software<ref name="processors">{{Cite news
|last= Davis
|first= Joshua
|title= The Crypto-Currency
|url= http://www.wired.com/magazine/2011/11/mf_bitcoin/all
|accessdate = 11 November 2011
|newspaper= Wired Magazine
|date= 10 November 2011
}}</ref> and developed the majority of the first implementation, Bitcoind, from 2007 to mid-2010.<ref name="code_start">{{cite web
|url= https://bitcointalk.org/index.php?topic=13.msg46#msg46
|title= Questions about Bitcoin
|publisher= Bitcoin forum
|date= 2009-12-10
}}</ref>

Node implementations include core software such as Bitcoind/Bitcoin-Qt, [[libbitcoin]], [[cbitcoin]]<ref>{{Cite web|title=cbitcoin|url=https://github.com/MatthewLM/cbitcoin|accessdate=3 October 2012}}</ref> and [[BitCoinJ|bitcoinj]].<ref>{{cite web
|url= http://news.slashdot.org/story/11/03/23/0210207/Google-Engineer-Releases-Open-Source-Bitcoin-Client
|title= Google Engineer Releases Open Source Bitcoin Client
|author= angry tapir, timothy
|date= 23 March 2011
|publisher= Slashdot
|accessdate = 2011-05-18
}}</ref><ref>{{cite web
|url= http://www.javaworld.com/javaworld/jw-01-2012/120110-bitcoin-for-beginners-3.html?page=1
|title= Bitcoin for beginners: The BitcoinJ API
|author= Dirk Merkel
|date= 10 January 2012
|publisher= JavaWorld
|accessdate = 2012-08-03
}}</ref>

Every node in the Bitcoin network collects all the unacknowledged transactions it knows of in a file called a ''block'', which also contains a reference to the previous valid block known to that node. It then appends a [[nonce]] value to this previous block and computes the SHA-256 cryptographic hash of the block and the appended nonce value. The node repeats this process until it adds a nonce that allows for the generation of a hash with a value lower than a specified ''target''. Because computers cannot practically reverse the hash function, finding such a nonce is hard and requires on average a predictable amount of repetitious trial and error. This is where the ''[[proof-of-work]]'' concept comes in to play. When a node finds such a solution, it announces it to the rest of the network. Peers receiving the new solved block validate it by computing the hash and checking that it really starts with the given number of zero bits (i.e., that the hash is within the target). Then they accept it and add it to the chain.

===Mining rewards===
In addition to receiving the pending transactions confirmed in the block, a generating node adds a ''generate'' transaction, which awards new Bitcoins to the operator of the node that generated the block. The system sets the payout of this generated transaction according to its defined inflation schedule. The miner that generates a block also receives the fees that users have paid as an incentive to give particular transactions priority for faster confirmation.<ref>[https://www.bitcoinmining.com Bitcoin Mining]</ref>

The network never creates more than a 50 BTC reward per block and this amount will decrease over time towards zero, such that no more than 21 million BTC will ever exist.<ref name="lwn" /> As this payout decreases, the incentive for users to run block-generating nodes is intended to change to earning [[#Transaction fees|transaction fees]].

===Mining pools===
{{main|Pooled mining}}

Bitcoin users often pool computational effort to increase the stability of the collected fees and subsidy they receive.<ref name="We Use Coins Mining">{{cite web|title=About Bitcoin Mining|url=https://www.weusecoins.com/en/mining-guide/|publisher=We Use Coins|accessdate=27 May 2015}}</ref>

===Mining difficulty===
{{main|Difficulty}}

In order to throttle the creation of blocks, the difficulty of generating new blocks is adjusted over time. If mining output increases or decreases, the difficulty increases or decreases accordingly.

The adjustment is done by changing the threshold that a hash is required to be less than. A lower threshold means fewer possible hashes can be accepted, and thus a higher degree of difficulty. The target rate of block generation is one block every 10 minutes, or 2016 blocks every two weeks. Bitcoin changes the difficulty of finding a valid block every 2016 blocks, using the difficulty that would have been most likely to cause the prior 2016 blocks to have taken two weeks to generate, according to the timestamps on the blocks. Technically, this is done by modeling the generation of Bitcoins as Poisson process. All nodes perform and enforce the same difficulty calculation.

Difficulty is intended as an automatic stabilizer allowing mining for Bitcoins to remain profitable in the long run for the most efficient miners, independently of the fluctuations in demand of Bitcoin in relation to other currencies.

===Mining hardware===
{{main|Mining Hardware Comparison}}

Bitcoins used to be mined through Intel/AMD CPUs. {{As of | 2012}}, mining has gradually moved to [[GPU]] and [[FPGA]] hardware.<ref name="bitcoinmag-butterfly" /> [[Application-specific integrated circuit|ASIC]]-based hardware for Bitcoin mining has been announced by several manufacturers who intend to ship products from late 2012 to early 2013.<ref name="bitcoinmag-butterfly">{{Cite web|title=Bitpay Breaks Daily Volume Record with Butterfly ASIC mining release|url=http://bitcoinmagazine.net/bitpay-breaks-daily-volume-record-with-butterfly-asic-mining-release/|publisher=Bitcoin Magazine}}</ref>

==Concerns==

===As an investment===
Bitcoin describes itself as an experimental digital currency. Reuben Grinberg has noted that Bitcoin's supporters have argued that Bitcoin is neither a security or an investment because it fails to meet the criteria for either category.<ref name="grinberg">{{cite web | url=http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1817857 | title=Bitcoin: An Innovative Alternative Digital Currency | publisher=SSRN | date=9 December 2011 | accessdate=4 December 2012 | author=Grinberg, Reuben}}</ref> Although it is a virtual currency, some people see it as an investment<ref name="cnbc">{{cite web | url=http://www.cnbc.com/id/45030812/The_Pros_And_Cons_Of_Biting_on_Bitcoins | title=The Pros And Cons Of Biting on Bitcoins | publisher=CNBC | date=23 November 2011 | accessdate=4 December 2012 | author=Gustke, Constance}}</ref> or accuse it of being a form of investment fraud known as a Ponzi scheme.<ref>{{cite web |url=http://www.theregister.co.uk/2011/06/08/bitcoin_under_attack/ |title=US senators draw a bead on Bitcoin |last1=Chirgwin |first1=Richard |date=8 June 2011 |publisher=The Register |accessdate=14 November 2012}}</ref><ref>{{cite web |url=http://uk.reuters.com/article/2012/04/01/uk-traders-bitcoin-idUKBRE8300JL20120401 |title=Bitcoin, the City traders' anarchic new toy |last1=O'Leary |first1=Naomi |date=2 April 2012 |publisher=Reuters |accessdate=14 November 2012}}</ref> A report by the European Central Bank, using the U.S. Securities and Exchange Commission's definition of a Ponzi scheme, found that the use of bitcoins shares some characteristics with Ponzi schemes, but also has characteristics of its own which contradict several common aspects of Ponzi schemes.<ref name="ecbreport">{{cite web | url=http://www.ecb.europa.eu/pub/pdf/other/virtualcurrencyschemes201210en.pdf | title=Virtual Currency Schemes | publisher=European Central Bank | date=October 2012 | accessdate=4 December 2012}}</ref>

===Privacy===
Because transactions are broadcast to the entire network, they are inherently public. Unlike regular banking,<ref>{{cite web
|url= http://spectrum.ieee.org/computing/software/bitcoin-the-cryptoanarchists-answer-to-cash/0
|title= Bitcoin: The Cryptoanarchists' Answer to Cash
|publisher= IEEE.org
|date= June 2012
|accessdate = 2012-06-05
}}</ref> which preserves customer privacy by keeping transaction records private, loose transactional privacy is accomplished in Bitcoin by using many unique addresses for every wallet, while at the same time publishing all transactions. As an example, if Alice sends 123.45 BTC to Bob, the network creates a public record that allows anyone to see that 123.45 has been sent from one address to another. However, unless Alice or Bob make their ownership of these addresses known, it is difficult for anyone else to connect the transaction with them. However, if someone connects an address to a user at any point they could follow back a series of transactions as each participant likely knows who paid them and may disclose that information on request or under duress.

It can be difficult to associate Bitcoin identities with real-life identities.<ref name="An Analysis of Anonymity in the Bitcoin System">Fergal Reid and Martin Harrigan (24 July 2011). [http://anonymity-in-bitcoin.blogspot.com/2011/07/bitcoin-is-not-anonymous.html An Analysis of Anonymity in the Bitcoin System]. An Analysis of Anonymity in the Bitcoin System.</ref> This property makes Bitcoin transactions attractive to sellers of illegal products.<ref name="Forbes">Andy Greenberg (20 April 2011). [http://www.forbes.com/forbes/2011/0509/technology-psilocybin-bitcoins-gavin-andresen-crypto-currency.html Crypto Currency]. Forbes Magazine.</ref><ref>{{cite web
|last= Madrigal
|first= Alexis
|title= Libertarian Dream? A Site Where You Buy Drugs With Digital Dollars
|publisher= The Atlantic Monthly
|date= 2011-06-01
|url= http://www.theatlantic.com/technology/archive/2011/06/libertarian-dream-a-site-where-you-buy-drugs-with-digital-dollars/239776/
|accessdate = 2011-06-05
}}</ref>

===Illicit use===

====Cracking====
The cracking organization "LulzSec" accepted donations in Bitcoin, having said that the group "needs Bitcoin donations to continue their hacking efforts".<ref name="CNET">{{cite web
|last= Reisinger
|first= Don
|url= http://news.cnet.com/8301-13506_3-20070268-17/senators-target-bitcoin-currency-citing-drug-sales/
|title= Senators target Bitcoin currency, citing drug sales | The Digital Home – CNET News
|publisher= News.cnet.com
|date= 2011-06-09
|accessdate = 2011-06-22
}}</ref><ref>{{cite news
|last= Olson
|first= Parmy
|url= http://blogs.forbes.com/parmyolson/2011/06/06/lulzsec-hackers-posts-sony-dev-source-code-get-7k-donation/
|title= LulzSec Hackers Post Sony Dev. Source Code, Get $7K Donation – Parmy Olson – Disruptors – Forbes
|publisher= Blogs.forbes.com
|date= 6 June 2011
|accessdate = 2011-06-22
}}</ref>

====Silk Road====
[[Silk Road]] is an anonymous black market that uses only the Bitcoin.<ref name="npr-06-12-11">
{{Cite news
|url= http://www.npr.org/2011/06/12/137138008/silk-road-not-your-fathers-amazon-com
|date= 12 June 2011
|newspaper= NPR
|title= Silk Road: Not Your Father's Amazon.com
|author= Staff
}}</ref>

In a 2011 letter to Attorney General Eric Holder and the Drug Enforcement Administration, senators Charles Schumer of New York and Joe Manchin of West Virginia called for an investigation into Silk Road and the Bitcoin.<ref name="npr-06-12-11"/>
Schumer described the use of Bitcoins at Silk Road as a form of money laundering.<ref name="ars-06-08-11"/>

====Botnet mining====
In June 2011, Symantec warned about the possibility of botnets engaging in covert "mining" of Bitcoins,<ref>{{Cite web|author=Updated: 17 June 2011 | Translations available: 日本語 |url=http://www.symantec.com/connect/blogs/bitcoin-botnet-mining |title=Bitcoin Botnet Mining | Symantec Connect Community |publisher=Symantec.com |date=2011-06-17 |accessdate = 2012-01-24}}</ref><ref>{{Cite web|url=http://www.zdnet.com/blog/security/researchers-find-malware-rigged-with-bitcoin-miner/8934 |title=Researchers find malware rigged with Bitcoin miner |publisher=ZDNet |date=2011-06-29 |accessdate = 2012-01-24}}</ref> consuming computing cycles, using extra electricity and possibly increasing the temperature of the computer. Later that month, the Australian Broadcasting Corporation caught an employee using the company's servers to generate Bitcoins without permission.<ref>{{Cite web|url=http://thenextweb.com/au/2011/06/23/abc-employee-caught-mining-for-bitcoins-on-company-servers/ |title=ABC employee caught mining for Bitcoins on company servers |publisher=The Next Web |date=2011-06-23 |accessdate = 2012-01-24}}</ref> Some malware also uses the parallel processing capabilities of the GPUs built into many modern-day video cards.<ref>{{Cite news |url=http://www.theregister.co.uk/2011/08/16/gpu_bitcoin_brute_forcing/ |title=Malware mints virtual currency using victim's GPU |date=16 August 2011|first=Dan |last=Goodin }}</ref> In mid August 2011, Bitcoin miner botnets were found;<ref>{{Cite web|url=http://www.infosecurity-magazine.com/view/20211/researcher-discovers-distributed-bitcoin-cracking-trojan-malware/ |title=Infosecurity – Researcher discovers distributed bitcoin cracking trojan malware |publisher=Infosecurity-magazine.com |date=2011-08-19 |accessdate = 2012-01-24}}</ref> trojans infecting Mac OS X have also been uncovered.<ref>{{Cite web|url=http://www.techworld.com.au/article/405849/mac_os_x_trojan_steals_processing_power_produce_bitcoins |title=Mac OS X Trojan steals processing power to produce Bitcoins – sophos, security, malware, Intego – Vulnerabilities – Security |publisher=Techworld |date=2011-11-01 |accessdate = 2012-01-24}}</ref>

===Theft and fraud===
On 19 June 2011, a security breach of the Mt.Gox (an acronym for ''M''agic: ''T''he ''G''athering ''O''nline E''x''change, its original purpose) Bitcoin Exchange caused the price of a Bitcoin to briefly drop to US$0.01 on the Mt.Gox exchange (though it remained unaffected on other exchanges) after a hacker allegedly used credentials from a Mt.Gox auditor's compromised computer to illegally transfer a large number of Bitcoins to him- or herself and sell them all, creating a massive "ask" order at any price. Within minutes the price rebounded to over $15 before Mt.Gox shut down their exchange and canceled all trades that happened during the hacking period.<ref>[https://mtgox.com/press_release_20110630.html Clarification of Mt Gox Compromised Accounts and Major Bitcoin Sell-Off]</ref><ref>[http://www.youtube.com/watch?v=T1X6qQt9ONg YouTube. Bitcoin Report]</ref> The exchange rate of Bitcoins quickly returned to near pre-crash values.<ref name="mick">Jason Mick, 19 June 2011, [http://www.dailytech.com/Inside+the+MegaHack+of+Bitcoin+the+Full+Story/article21942.htm Inside the Mega-Hack of Bitcoin: the Full Story], DailyTech</ref><ref>Timothy B. Lee, 19 June 2011, [http://arstechnica.com/tech-policy/news/2011/06/bitcoin-price-plummets-on-compromised-exchange.ars Bitcoin prices plummet on hacked exchange], Ars Technica</ref><ref>Mark Karpeles, 20 June 2011, [https://support.mtgox.com/entries/20208066-huge-bitcoin-sell-off-due-to-a-compromised-account-rollback Huge Bitcoin sell off due to a compromised account – rollback], Mt.Gox Support</ref><ref name="register1">{{Cite news
|title= Bitcoin collapses on malicious trade – Mt Gox scrambling to raise the Titanic
|url= http://www.theregister.co.uk/2011/06/19/bitcoin_values_collapse_again/
|date= 2011-06-19
|author= Chirgwin, Richard
|publisher= The Register
}}</ref> Accounts with the equivalent of more than USD 8,750,000 were affected.<ref name="mick" />

In July 2011, The operator of Bitomat, the third largest Bitcoin exchange, announced that he lost access to his wallet.dat file with about 17,000 BitCoins (roughly equivalent to 220,000 USD at that time). He announced that he would sell the service for the missing amount, aiming to use funds from the sale to refund his customers.<ref>[http://siliconangle.com/blog/2011/08/01/third-largest-bitcoin-exchange-bitomat-lost-their-wallet-over-17000-bitcoins-missing/ Third Largest Bitcoin Exchange Bitomat Lost Their Wallet, Over 17,000 Bitcoins Missing]. SiliconAngle</ref>

In August 2011, MyBitcoin, one of popular Bitcoin transaction processors, declared that it was hacked, which resulted in it being shut down, with paying 49% on customer deposits, leaving more than 78,000 BitCoins (roughly equivalent to 800,000 USD at that time) unaccounted for.<ref>[http://betabeat.com/2011/08/mybitcoin-spokesman-finally-comes-forward-what-did-you-think-we-did-after-the-hack-we-got-shitfaced/ MyBitcoin Spokesman Finally Comes Forward: “What Did You Think We Did After the Hack? We Got Shitfaced”]. BetaBeat</ref><ref>[http://betabeat.com/2011/08/search-for-owners-of-mybitcoin-loses-steam/ Search for Owners of MyBitcoin Loses Steam]. BetaBeat</ref>

In early August 2012, a lawsuit was filed in San Francisco court against Bitcoinica, claiming about 460,000 USD from the company. Bitcoinica was hacked twice in 2012, which led to allegations of neglecting the safety of customers' money and cheating them out of withdrawal requests.<ref>[http://arstechnica.com/tech-policy/2012/08/bitcoinica-users-sue-for-460k-in-lost-bitcoins/ Bitcoinica users sue for $460k in lost Bitcoins]. Arstechnica</ref><ref>[http://spectrum.ieee.org/tech-talk/computing/networks/first-bitcoin-lawsuit-filed-in-san-francisco First Bitcoin Lawsuit Filed In San Francisco]. IEEE Spectrum</ref>

In late August 2012, Bitcoin Savings and Trust was shut down by the owner, allegedly leaving around $5.6 million in debts; this led to allegations of the operation being a Ponzi scheme.<ref>{{Cite web|title=Bitcoin ponzi scheme – investors lose $5 million USD in online hedge fund|url=http://rt.com/usa/news/investors-currency-digital-fund-868/|publisher=RT}}</ref><ref>{{Cite web|last=Jeffries|first=Adrianne|title=Suspected multi-million dollar Bitcoin pyramid scheme shuts down, investors revolt|url=http://www.theverge.com/2012/8/27/3271637/bitcoin-savings-trust-pyramid-scheme-shuts-down|publisher=The Verge}}</ref><ref>{{Cite web|last=Mick|first=Jason|title="Pirateat40" Makes Off $5.6M USD in BitCoins From Pyramid Scheme|url=http://www.dailytech.com/Pirateat40+Makes+Off+56M+USD+in+BitCoins+From+Pyramid+Scheme/article25538.htm|publisher=DailyTech}}</ref><ref>[http://pandodaily.com/2012/08/31/bitcoin-how-a-virtual-currency-became-real-with-a-5-6m-fraud/ Bitcoin: How a Virtual Currency Became Real with a $5.6M Fraud]. PandoDaily</ref> In September 2012, it was reported that U.S. Securities and Exchange Commission has started an investigation on the case.<ref>[http://blogs.telegraph.co.uk/technology/willardfoxton2/100007836/bitcoin-pirate-scandal-sec-steps-in-amid-allegations-that-the-whole-thing-was-a-ponzi-scheme/ Bitcoin 'Pirate' scandal: SEC steps in amid allegations that the whole thing was a Ponzi scheme ]. The Telegraph</ref>

In September 2012, Bitfloor Bitcoin exchange also reported being hacked, with 24,000 BitCoins (roughly equivalent to 250,000 USD) stolen. As a result, Bitfloor suspended operations.<ref>[http://www.bbc.co.uk/news/technology-19486695 Bitcoin theft causes Bitfloor exchange to go offline]. BBC</ref><ref>[http://www.theverge.com/2012/9/5/3293375/bitfloor-bitcoin-exchange-suspended-theft Bitcoin exchange BitFloor suspends operations after $250,000 theft Bitcoin exchange BitFloor suspends operations after $250,000 theft]. The Verge</ref> The same month, Bitfloor resumed operations, with its founder saying that he reported the theft to FBI, and that he is planning to repay the victims, though the time frame for such repayment is unclear.<ref>[http://www.pcworld.com/article/2010586/bitcoin-exchange-back-online-after-hack.html?tk=rel_news Bitcoin exchange back online after hack]. PCWorld</ref>

===Taxation===
In September 2012, the Intra-European Organization of Tax Administrations (IOTA), in Tbilisi, Georgia, held a workshop titled "Auditing Individuals and Legal Entities in the Use of e-Money." The workshop was attended by representatives from 23 countries.<ref name="BitCoin Tax issues Oct 2012">{{cite journal | title=2012 TNT 209-4 NEWS ANALYSIS: VIRTUAL CURRENCY: A NEW WORRY FOR TAX ADMINISTRATORS?. (Release Date: OCTOBER 17, 2012) (Doc 2012-21516) | author=Stewart, David D. and Soong Johnston, Stephanie D. | journal=Tax Notes Today | year=2012 | month=October 29 | volume=2012 TNT 209-4 | issue=2012 TNT 209-4}}</ref> Jerry Taylor, IOTA's technical taxation expert, said, "There's an awful lot happening on the Internet environment which is fascinating at the moment and introducing new challenges for auditors when it comes to virtual currency."<ref name="BitCoin Tax issues Oct 2012">{{cite journal | title=2012 TNT 209-4 NEWS ANALYSIS: VIRTUAL CURRENCY: A NEW WORRY FOR TAX ADMINISTRATORS?. (Release Date: OCTOBER 17, 2012) (Doc 2012-21516) | author=Stewart, David D. and Soong Johnston, Stephanie D. | journal=Tax Notes Today | year=2012 | month=October 29 | volume=2012 TNT 209-4 | issue=2012 TNT 209-4}}</ref> Bitcoin was mentioned during the workshop.<ref name="BitCoin Tax issues Oct 2012">{{cite journal | title=2012 TNT 209-4 NEWS ANALYSIS: VIRTUAL CURRENCY: A NEW WORRY FOR TAX ADMINISTRATORS?. (Release Date: OCTOBER 17, 2012) (Doc 2012-21516) | author=Stewart, David D. and Soong Johnston, Stephanie D. | journal=Tax Notes Today | year=2012 | month=October 29 | volume=2012 TNT 209-4 | issue=2012 TNT 209-4}}</ref>

Matthew Elias, founder of the [[Cryptocurrency Legal Advocacy Group]] (CLAG) published "Staying Between the Lines: A Survey of U.S. Income Taxation and its Ramifications on Cryptocurrencies", which discusses "the taxability of cryptocurrencies such as bitcoin."<ref name="BitCoin Tax issues Oct 2012">{{cite journal | title=2012 TNT 209-4 NEWS ANALYSIS: VIRTUAL CURRENCY: A NEW WORRY FOR TAX ADMINISTRATORS?. (Release Date: OCTOBER 17, 2012) (Doc 2012-21516) | author=Stewart, David D. and Soong Johnston, Stephanie D. | journal=Tax Notes Today | year=2012 | month=October 29 | volume=2012 TNT 209-4 | issue=2012 TNT 209-4}}</ref> CLAG "stressed the importance for taxpayers to determine on their own whether taxes are due on a bitcoin-related transaction based on whether one has "experienced a realization event."<ref name="BitCoin Tax issues Oct 2012">{{cite journal | title=2012 TNT 209-4 NEWS ANALYSIS: VIRTUAL CURRENCY: A NEW WORRY FOR TAX ADMINISTRATORS?. (Release Date: OCTOBER 17, 2012) (Doc 2012-21516) | author=Stewart, David D. and Soong Johnston, Stephanie D. | journal=Tax Notes Today | year=2012 | month=October 29 | volume=2012 TNT 209-4 | issue=2012 TNT 209-4}}</ref> Such examples are "when a taxpayer has provided a service in exchange for bitcoins, a realization event has probably occurred, and any gain or loss would likely be calculated using fair market values for the service provided."<ref name="BitCoin Tax issues Oct 2012">{{cite journal | title=2012 TNT 209-4 NEWS ANALYSIS: VIRTUAL CURRENCY: A NEW WORRY FOR TAX ADMINISTRATORS?. (Release Date: OCTOBER 17, 2012) (Doc 2012-21516) | author=Stewart, David D. and Soong Johnston, Stephanie D. | journal=Tax Notes Today | year=2012 | month=October 29 | volume=2012 TNT 209-4 | issue=2012 TNT 209-4}}</ref>

[[Peter Vessenes]], [[Bitcoin Foundation|Bitcoin Foundation's]] executive director, said, since the foundation is trying to pay for everything in bitcoin, including salaries, "How do we W-2 someone for their bitcoins? Do we mark-to-market every time a transfer happens? Payroll companies cringe."<ref name="BitCoin Tax issues Oct 2012">{{cite journal | title=2012 TNT 209-4 NEWS ANALYSIS: VIRTUAL CURRENCY: A NEW WORRY FOR TAX ADMINISTRATORS?. (Release Date: OCTOBER 17, 2012) (Doc 2012-21516) | author=Stewart, David D. and Soong Johnston, Stephanie D. | journal=Tax Notes Today | year=2012 | month=October 29 | volume=2012 TNT 209-4 | issue=2012 TNT 209-4}}</ref> The Bitcoin Foundation hopes "to push for solid guidance about its legal and tax treatment." [[Patrick Murck]], legal counsel for the Bitcoin Foundation, said he would like "to help regulators understand the technology better so they can make better decisions."<ref name="BitCoin Tax issues Oct 2012">{{cite journal | title=2012 TNT 209-4 NEWS ANALYSIS: VIRTUAL CURRENCY: A NEW WORRY FOR TAX ADMINISTRATORS?. (Release Date: OCTOBER 17, 2012) (Doc 2012-21516) | author=Stewart, David D. and Soong Johnston, Stephanie D. | journal=Tax Notes Today | year=2012 | month=October 29 | volume=2012 TNT 209-4 | issue=2012 TNT 209-4}}</ref> Murck said, "Bitcoin has the potential to become much more than a niche currency, but it needs the guidance and understanding of regulators." and "The full potential of bitcoin could be realized through clearer guidelines and a better understanding by financial and tax regulators." and "Part of making that happen is to talk to regulators, the IRS, and tax professionals and helping them understand that bitcoin is not this nefarious thing, it's just software, it's a community, and there's nothing inherently nefarious about either of those things."<ref name="BitCoin Tax issues Oct 2012">{{cite journal | title=2012 TNT 209-4 NEWS ANALYSIS: VIRTUAL CURRENCY: A NEW WORRY FOR TAX ADMINISTRATORS?. (Release Date: OCTOBER 17, 2012) (Doc 2012-21516) | author=Stewart, David D. and Soong Johnston, Stephanie D. | journal=Tax Notes Today | year=2012 | month=October 29 | volume=2012 TNT 209-4 | issue=2012 TNT 209-4}}</ref>

==See Also==
* [[Introduction]]
* [[Getting started]]
* [[Using_Bitcoin|Detailed tutorial]]
* [[FAQ]]
* [https://www.weusecoins.com What Is Bitcoin?]
* [https://www.bitcoinmining.com What Is Bitcoin Mining?]

==References==
<references />

[[Category:Digital currencies]]
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[[es:Bitcoin]][[de:Bitcoin]]

Help:FAQ

2015-07-07T15:34:27Z

Sunnankar: /* What is Bitcoin? */

Here you will find answers to the most commonly asked questions.

== General ==
=== What is Bitcoin? ===
[https://www.weusecoins.com Bitcoin] is a distributed peer-to-peer digital currency that can be transferred instantly and securely between any two people in the world. It's like electronic cash that you can use to pay friends or merchants.

=== What are bitcoins? ===
Bitcoins are the unit of currency of the Bitcoin system. A commonly used shorthand for this is “BTC” to refer to a price or amount (e.g. “100 BTC”).
There are such things as [[physical bitcoins]], but ultimately, a bitcoin is just a number associated with a [[Address|Bitcoin Address]]. A physical bitcoin is simply an object, such as a coin, with the number carefully embedded inside. See also an [[Introduction|easy intro]] to Bitcoin.

=== How can I get bitcoins? ===

There are a variety of ways to acquire bitcoins:
* You can buy bitcoins from [http://coinbase.com/ Coinbase], [http://cubits.com/ Cubits], [[File:BIPS.gif|20px|link=https://bipsmarket.com]] [https://bipsmarket.com BIPS Market] or [http://gocelery.com/ Celery] .
* Accept bitcoins as payment for goods or services.
* The most common way to buy bitcoins are the [[Buying bitcoins|Bitcoin Exchanges]]
* Visit [http://bitcoinx.io bitcoinx.io] for peer-to-peer ratings and reviews of bitcoin exchanges to see where to buy bitcoins
* There are several services where you can [[Buying_Bitcoins_(the_noob_version)|trade them]] for traditional currency.
* Find someone to trade cash for bitcoins in-person through a [https://en.bitcoin.it/wiki/Category:Directories local directory].
* Participate in a [[Pooled mining|mining pool]].
* If you have a lot of mining hardware, you can solo mine and attempt to create a new [[block]] (currently yields 25 bitcoins plus transaction fees).
* Visit sites that provide [[Trade#Free_Samples_and_Offers|free samples and offers]].
* Visit [http://wheretobuycryptocoins.com WhereToBuyCryptoCoins.com] to get a guide how to start with bitcoins and cryptocurrency in general. Shows a list of markets, faucets, exchanges, miner's pools and more.

===Does Bitcoin guarantee an influx of free money?===

Since Bitcoin is a new technology, what it is and how it works may be initially unclear. Bitcoin is sometimes presented as being one of three things:
<ol style="list-style-type: upper-alpha;">
<li>Some sort of online 'get-rich-quick' scam.</li>
<li>A loophole in the market economy, the installation of which guarantees a steady influx of cash.</li>
<li>A sure investment that will almost certainly yield a profit.</li>
</ol>
In fact, none of the above are true. Let's look at them independently.

;Is Bitcoin a 'get-rich-quick' scheme?
:If you've spent much time on the Internet, you've probably seen ads for many 'get-rich-quick' schemes. These ads usually promise huge profits for a small amounts of easy work. Such schemes are usually pyramid/matrix-style schemes that make money from their own employees and offer nothing of any real value. Most convince one to buy packages that will make them earn hundreds a day, which in fact have the buyer distribute more such ads, and make minute profits.

:Bitcoin is in no way similar to these schemes. Bitcoin doesn't promise windfall profits. There is no way for the developers to make money from your involvement or to take money from you. That bitcoins are nearly impossible to acquire without the owner's consent represents one of its greatest strengths. Bitcoin is an experimental, virtual currency that may succeed or may fail. None of its developers expect to get rich off of it.

:A more detailed answer to this question can be found [http://bitcointalk.org/?topic=7815.0 here].

;Will I make money by installing the client?
:Most people who use Bitcoin don't earn anything by doing so, and the default client has no built-in way to earn Bitcoins. A small minority of people with dedicated, high-performance hardware do earn some Bitcoins by "''mining''" (generating new bitcoins, see [[#What is mining?|What is mining?]]) with special software, but joining Bitcoin shouldn't be construed as being the road to riches. Most Bitcoin users get involved because they find the project conceptually interesting and don't earn anything by doing so. This is also why you won't find much speculation about the political or economic repercussions of Bitcoin anywhere on this site: Bitcoin developers owe their dedication to the project's intellectual yieldings more than to those of a monetary nature. Bitcoin is still taking its first baby steps; it may go on to do great things but right now it only has something to offer those chasing conceptually interesting projects or bleeding edge technology.

;As an investment, is Bitcoin a sure thing?
:Bitcoin is a new and interesting electronic currency, the value of which is not backed by any single government or organization. Like other currencies, it is worth something partly because people are willing to trade it for goods and services. Its exchange rate fluctuates continuously, and sometimes wildly. It lacks wide acceptance and is vulnerable to manipulation by parties with modest funding. Security incidents such as website and account compromise may trigger major sell-offs. Other fluctuations can build into positive feedback loops and cause much larger exchange rate fluctuations. Anyone who puts money into Bitcoin should understand the risk they are taking and consider it a high-risk currency. Later, as Bitcoin becomes better known and more widely accepted, it may stabilize, but for the time being it is unpredictable. Any investment in Bitcoin should be done carefully and with a clear plan to manage the risk.

=== Can I buy bitcoins with Paypal? ===

It is possible to buy [[physical bitcoins]] with PayPal but it is otherwise difficult and/or expensive to do so for non-physical bitcoins, because of significant risk to the seller.

While it is possible to find an individual who wishes to sell Bitcoin to you via Paypal, (perhaps via [http://www.bitcoin-otc.com/ #bitcoin-otc] ) most exchanges do not allow funding through PayPal. This is due to repeated cases where someone pays for bitcoins with Paypal, receives their bitcoins, and then fraudulently complains to Paypal that they never received their purchase. PayPal often sides with the fraudulent buyer in this case, which means any seller needs to cover that risk with higher fees or refuse to accept PayPal altogether.

Buying Bitcoins from individuals this way is still possible, but requires the seller to have some trust that the buyer will not file a claim with PayPal to reverse the payment.

=== Where can I find a forum to discuss Bitcoin? ===

Please visit the [[Bitcoin Wiki:Community_portal#Bitcoin_Community_Forums_on_various_platforms|Community Portal]] for links to Bitcoin-related forums.

=== How are new bitcoins created? ===

New bitcoins are generated by the network through the process of "[[#What is mining?|''mining'']]". In a process that is similar to a continuous raffle draw, mining nodes on the network are awarded bitcoins each time they find the solution to a certain mathematical problem (and thereby create a new [[block]]). Creating a block is a [[proof of work]] with a difficulty that varies with the overall strength of the network. The reward for solving a block is [[Controlled Currency Supply|automatically adjusted]] so that, ideally, every four years of operation of the Bitcoin network, half the amount of bitcoins created in the prior 4 years are created. A maximum of {{formatnum:10499889.80231183}} bitcoins were created in the first 4 (approx.) years from January 2009 to November 2012. Every four years thereafter this amount halves, so it should be {{formatnum:5250000}} over years 4-8, {{formatnum:2625000}} over years 8-12, and so on. Thus the total number of bitcoins in existence can never exceed {{formatnum:20999839.77085749}} and counting. See [[Controlled Currency Supply]].

Blocks are [[Mining|mined]] every 10 minutes, on average and for the first four years ({{formatnum:210000}} blocks) each block included 50 new bitcoins. As the amount of processing power directed at mining changes, the difficulty of creating new bitcoins changes. This difficulty factor is calculated every 2016 blocks and is based upon the time taken to generate the previous 2016 blocks. See [[Mining]].

=== What's the current total number of bitcoins in existence? ===

[http://blockexplorer.com/q/totalbc Current count]. Also see [https://blockchain.info/charts/total-bitcoins Total bitcoins in circulation chart]

The number of blocks times the coin value of a block is the number of coins in existence. The coin value of a block is 50 BTC for each of the first {{formatnum:210000}} blocks, 25 BTC for the next {{formatnum:210000}} blocks, then 12.5 BTC, 6.25 BTC and so on.

=== How divisible are bitcoins? ===

A bitcoin can be divided down to 8 decimal places. Therefore, 0.00000001 BTC is the smallest amount that can be handled in a transaction. If necessary, the protocol and related software can be modified to handle even smaller amounts.

=== What do I call the various denominations of bitcoin? ===

Unlike most currencies, Bitcoin amounts are highly divisible. This has led to a desire to create names for smaller denominations of bitcoin amounts, especially since transactions involving whole bitcoins are no longer quite so common. Bitcoin is decentralized, so there is no organization that can set official names for units. Therefore, there are many different units with varying degrees of popularity. As of 2014, the most common units are bitcoins, bits, and satoshi: 1 bitcoin = 1 000 000.00 bits = 100 000 000 satoshi.

The '''bitcoin''' (abbreviated '''BTC''' or '''XBT''') is the unit that was used in the original Bitcoin wallet software created by [[Satoshi Nakamoto]]. There is nothing particularly special about this unit, but it is by far the most common unit due to tradition.

The smallest value that the Bitcoin network supports sending is the '''[[satoshi (unit)|satoshi]]''' (sometimes abbreviated '''sat'''), one hundred-millionth (0.000 000 01) of a bitcoin. In other words, the network does not support sending fractions of a satoshi. Since it is a hard limit, it seems natural to use it as a unit, though it currently has very little value. The unit was named in honor of Bitcoin's creator after he left -- he was not so vain as to name a unit after himself. The plural of satoshi is satoshi: "Send me 100 satoshi".

Another common unit is the '''[[bit (unit)|bit]]''', one millionth (0.000 001) of a bitcoin. This unit is the same as a microbitcoin (μBTC). Bits are seen by some as especially logical because they have two-decimal precision like most fiat currencies. You can send 1.23 bits, but not 1.234 bits due to the network's limited precision.

It is also fairly common to use SI prefixes:

* 0.01 BTC = 1 cBTC = 1 centibitcoin (also referred to as bitcent)
* 0.001 BTC = 1 mBTC = 1 millibitcoin (also referred to as mbit (pronounced em-bit) or millibit or even bitmill)
* 0.000 001 BTC = 1 μBTC = 1 microbitcoin (also referred to as ubit (pronounced yu-bit) or microbit)

For an overview of all proposed units of Bitcoin (including less common and niche units), see [[Units]].

Further discussion on this topic can be found on the forums here:

* [https://bitcointalk.org/index.php?topic=14438.msg195287#msg195287 We need names]
* [https://bitcointalk.org/index.php?topic=8282.0 What to call 0.001 BTC]

=== How does the halving work when the number gets really small? ===

Eventually the reward will go from 0.00000001 BTC to zero and no more bitcoins will be created.

The block reward calculation is done as a right bitwise shift of a 64-bit signed integer, which means it is divided by two and rounded down. The integer is equal to the value in BTC * 100,000,000 since internally in the reference client software, all Bitcoin balances and values are stored as unsigned integers.

With an initial block reward of 50 BTC, it will take many 4-year periods for the block reward to reach zero.

=== How long will it take to generate all the coins? ===

The last block that will generate coins will be block #6,929,999 which should be generated at or near the year 2140. The total number of coins in circulation will then remain static at 20,999,999.9769 BTC.

Even if the allowed precision is expanded from the current 8 decimals, the total BTC in circulation will always be slightly below 21 million (assuming everything else stays the same). For example, with 16 decimals of precision, the end total would be 20,999,999.999999999496 BTC.

=== If no more coins are going to be generated, will more blocks be created? ===

Absolutely! Even before the creation of coins ends, the use of [[transaction fee|transaction fees]] will likely make creating new blocks more valuable from the fees than the new coins being created. When coin generation ends, these fees will sustain the ability to use bitcoins and the Bitcoin network. There is no practical limit on the number of blocks that will be mined in the future.

=== But if no more coins are generated, what happens when Bitcoins are lost? Won't that be a problem? ===

Because of the law of supply and demand, when fewer bitcoins are available the ones that are left will be in higher demand, and therefore will have a higher value. So, as Bitcoins are lost, the remaining bitcoins will eventually increase in value to compensate. As the value of a bitcoin increases, the number of bitcoins required to purchase an item '''de'''creases. This is a [[Deflationary spiral|deflationary economic model]]. As the average transaction size reduces, transactions will probably be denominated in sub-units of a bitcoin such as millibitcoins ("Millies") or microbitcoins ("Mikes").

The Bitcoin protocol uses a base unit of one hundred-millionth of a Bitcoin ("a Satoshi"), but unused bits are available in the protocol fields that could be used to denote even smaller subdivisions.

=== If every transaction is broadcast via the network, does Bitcoin scale? ===
The Bitcoin protocol allows lightweight clients that can use Bitcoin without downloading the entire transaction history. As traffic grows and this becomes more critical, implementations of the concept will be developed. Full network nodes will at some point become a more specialized service.

With some modifications to the software, full Bitcoin nodes could easily keep up with both VISA and MasterCard combined, using only fairly modest hardware (a single high end server by todays standards). It is worth noting that the MasterCard network is structured somewhat like Bitcoin itself - as a peer to peer broadcast network.

Learn more about [[Scalability]].

==Economy==
=== Where does the value of Bitcoin stem from? What backs up Bitcoin? ===
Bitcoins have value because they are useful and because they are [[Controlled Currency Supply|scarce]]. As they are accepted by more merchants, their value will [http://en.wikipedia.org/wiki/Sticky_%28economics%29 stabilize]. See the [[Trade|list of Bitcoin-accepting sites]].

When we say that a currency is backed up by gold, we mean that there's a promise in place that you can exchange the currency for gold. Bitcoins, like dollars and euros, are not backed up by anything except the variety of merchants that accept them.

It's a common misconception that Bitcoins gain their value from the cost of electricity required to generate them. Cost doesn't equal value – hiring 1,000 men to shovel a big hole in the ground may be costly, but not valuable. Also, even though scarcity is a critical requirement for a useful currency, it alone doesn't make anything valuable. For example, your fingerprints are scarce, but that doesn't mean they have any exchange value.

Alternatively it needs to be added that while the law of supply and demand applies it does not guarantee value of Bitcoins in the future. If confidence in Bitcoins is lost then it will not matter that the supply can no longer be increased, the demand will fall off with all holders trying to get rid of their coins. An example of this can be seen in cases of state currencies, in cases when the state in question dissolves and so no new supply of the currency is available (the central authority managing the supply is gone), however the demand for the currency falls sharply because confidence in its purchasing power disappears. Of-course Bitcoins do not have such central authority managing the supply of the coins, but it does not prevent confidence from eroding due to other situations that are not necessarily predictable.

=== Is Bitcoin a bubble? ===
Yes, in the same way as the euro and dollar are. They only have value in exchange and have no inherent value. If everyone suddenly stopped accepting your dollars, euros or bitcoins, the "bubble" would burst and their value would drop to zero. But that is unlikely to happen: even in Somalia, where the government collapsed 20 years ago, [http://en.wikipedia.org/wiki/Somali_shilling Somali shillings] are still accepted as payment.

=== Is Bitcoin a Ponzi scheme? ===
In a Ponzi Scheme, the founders persuade investors that they’ll profit. Bitcoin does not make such a guarantee. There is no central entity, just individuals building an economy.

A ponzi scheme is a zero sum game. Early adopters can only profit at the expense of late adopters. Bitcoin has possible win-win outcomes. Early adopters profit from the rise in value. Late adopters, and indeed, society as a whole, benefit from the usefulness of a stable, fast, inexpensive, and widely accepted p2p currency.

The fact that early adopters benefit more doesn't alone make anything a Ponzi scheme. All good investments in successful companies have this quality.

=== Doesn't Bitcoin unfairly benefit early adopters? ===
Early adopters in Bitcoin are taking a risk and invested resources in an unproven technology. By so doing, they help Bitcoin become what it is now and what it will be in the future (hopefully, a ubiquitous decentralized digital currency). It is only fair they will reap the benefits of their successful investment.

In any case, any bitcoin generated will probably change hands dozens of time as a medium of exchange, so the profit made from the initial distribution will be insignificant compared to the total commerce enabled by Bitcoin. Many of the earliest users of Bitcoin have traded their coins at valuations below $1 US, or other amounts which are small compared to contemporary prices.

===Won't loss of wallets and the finite amount of Bitcoins create excessive deflation, destroying Bitcoin? ===
Worries about Bitcoin being destroyed by deflation are not entirely unfounded. Unlike most currencies, which experience inflation as their founding institutions create more and more units, Bitcoin will likely experience gradual deflation with the passage of time. Bitcoin is unique in that only a small amount of units will ever be produced (twenty-one million to be exact), this number has been known since the project's inception, and the units are created at a predictable rate.

Also, Bitcoin users are faced with a danger that doesn't threaten users of any other currency: if a Bitcoin user loses his wallet, his money is gone forever, unless he finds it again. And not just to him; it's gone completely out of circulation, rendered utterly inaccessible to anyone. As people will lose their wallets, the total number of Bitcoins will slowly decrease.

Therefore, Bitcoin seems to be faced with a unique problem. Whereas most currencies inflate over time, Bitcoin will mostly likely do just the opposite. Time will see the irretrievable loss of an ever-increasing number of Bitcoins. An already small number will be permanently whittled down further and further. And as there become fewer and fewer Bitcoins, the laws of supply and demand suggest that their value will probably continually rise.

Thus Bitcoin is bound to once again stray into mysterious territory, because no one exactly knows what happens to a currency that grows continually more valuable. Many economists claim that a low level of inflation is a good thing for a currency, but nobody is quite sure about what might happens to one that continually deflates. Although deflation could hardly be called a rare phenomenon, steady, constant deflation is unheard of. There may be a lot of speculation, but no one has any hard data to back up their claims.

That being said, there is a mechanism in place to combat the obvious consequences. Extreme deflation would render most currencies highly impractical: if a single Canadian dollar could suddenly buy the holder a car, how would one go about buying bread or candy? Even pennies would fetch more than a person could carry. Bitcoin, however, offers a simple and stylish solution: infinite divisibility. Bitcoins can be divided up and trade into as small of pieces as one wants, so no matter how valuable Bitcoins become, one can trade them in practical quantities.

In fact, infinite divisibility should allow Bitcoins to function in cases of extreme wallet loss. Even if, in the far future, so many people have lost their wallets that only a single Bitcoin, or a fraction of one, remains, Bitcoin should continue to function just fine. No one can claim to be sure what is going to happen, but deflation may prove to present a smaller threat than many expect.

For more information, see the [[Deflationary spiral]] page.

=== What if someone bought up all the existing Bitcoins? ===
Bitcoin markets are competitive -- meaning the price of a bitcoin will rise or fall depending on supply and demand at certain price levels. Only a fraction of bitcoins issued to date are found on the exchange markets for sale. So even though technically, a buyer with lots of money could buy all the bitcoins offered for sale, unless those holding the rest of the bitcoins offer them for sale as well, even the wealthiest, most determined buyer can't get at them.

Additionally, new currency continues to be issued daily and will continue to do so for decades; though over time the rate at which they are issued declines to insignificant levels. Those who are mining aren't obligated to sell their bitcoins so not all bitcoins will make it to the markets even.

This situation doesn't suggest, however, that the markets aren't vulnerable to price manipulation. It doesn't take significant amounts of money to move the market price up or down, and thus Bitcoin remains a volatile asset.

===What if someone creates a new block chain, or a new digital currency that renders Bitcoin obsolete?===

That the block chain cannot be easily forked represents one of the central security mechanisms of Bitcoin. Given the choice between two block chains, a Bitcoin miner always chooses the longer one - that is to say, the one with the more complex hash. Thusly, it ensures that each user can only spend their bitcoins once, and that no user gets ripped off.

As a consequence of the block chain structure, there may at any time be many different sub-branches, and the possibility always exists of a transaction being over-written by the longest branch, if it has been recorded in a shorter one. The older a transaction is though, the lower its chances of being over-written, and the higher of becoming permanent. Although the block chain prevents one from spending more Bitcoins than one has, it means that transactions can be accidentally nullified.

A new block chain would leave the network vulnerable to [[double-spending|double-spend]] attacks. However, the creation of a viable new chain presents considerable difficulty, and the possibility does not present much of a risk.

Bitcoin will always choose the longer Block Chain and determines the relative length of two branches by the complexities of their hashes. Since the hash of each new block is made from that of the block preceding it, to create a block with a more complex hash, one must be prepared to do more computation than has been done by the entire Bitcoin network from the fork point up to the newest of the blocks one is trying to supersede. Needless to say, such an undertaking would require a very large amount of processing power and since Bitcoin is continually growing and expanding, it will likely only require more with the passage of time.

A much more distinct and real threat to the Bitcoin use is the development of other, superior virtual currencies, which could supplant Bitcoin and render it obsolete and valueless.

A great deal of careful thought and ingenuity has gone into the development of Bitcoin, but it is the first of its breed, a prototype, and vulnerable to more highly-evolved competitors. At present, any threatening rivals have yet to rear their heads; Bitcoin remains the first and foremost private virtual currency, but we can offer no guarantees that it will retain that position. It would certainly be in keeping with internet history for a similar system built from the same principles to supersede and cast Bitcoin into obsolescence, after time had revealed its major shortcomings. Friendster and Myspace suffered similar fates at the hand of Facebook, Napster was ousted by Limeware, Bearshare and torrent applications, and Skype has all but crushed the last few disciples of the Microsoft Messenger army.

This may sound rather foreboding, so bear in mind that the introduction of new and possibly better virtual currencies will not necessarily herald Bitcoin's demise. If Bitcoin establishes itself sufficiently firmly before the inception of the next generation of private, online currencies so as to gain widespread acceptance and general stability, future currencies may pose little threat even if they can claim superior design. This is known as the network effect.

=== Is Bitcoin open to value manipulation? ===

The current low market cap of Bitcoin means that any investor with deep enough pockets can significantly change/manipulate the rate. Is this a problem?

This is only a problem if you are investing in Bitcoin for short period of time. A manipulator can't change the fundamentals, and over a period of 5-10 years, the fundamentals will win over any short term manipulations.

==Sending and Receiving Payments==

=== Why do I have to wait 10 minutes before I can spend money I received? ===

10 minutes is the average time taken to find a block. It can be significantly more or less time than that depending on luck; 10 minutes is simply the average case.

[[Blocks]] (shown as "confirmations" in the GUI) are how the Bitcoin achieves consensus on who owns what. Once a block is found everyone agrees that you now own those coins, so you can spend them again. Until then it's possible that some network nodes believe otherwise, if somebody is attempting to defraud the system by reversing a transaction. The more confirmations a transaction has, the less risk there is of a reversal. Only 6 blocks or 1 hour is enough to make reversal computationally impractical. This is dramatically better than credit cards which can see chargebacks occur up to three months after the original transaction!

Ten minutes was specifically chosen by [[Satoshi]] as a tradeoff between first confirmation time and the amount of work wasted due to chain splits. After a block is mined, it takes time for other miners to find out about it, and until then they are actually competing against the new block instead of adding to it. If someone mines another new block based on the old block chain, the network can only accept one of the two, and all the work that went into the other block gets wasted. For example, if it takes miners 1 minute on average to learn about new blocks, and new blocks come every 10 minutes, then the overall network is wasting about 10% of its work. Lengthening the time between blocks reduces this waste.

As a thought experiment, what if the Bitcoin network grew to include Mars? From the farthest points in their orbits, it takes about 20 minutes for a signal to travel from Earth to Mars. With only 10 minutes between new blocks, miners on Mars would always be 2 blocks behind the miners on Earth. It would be almost impossible for them to contribute to the block chain. If we wanted collaborate with those kinds of delays, we would need at least a few hours between new blocks.

[[File:TransactionConfirmationTimesExample.PNG]]

=== Do you have to wait until my transactions are confirmed in order to buy or sell things with Bitcoin? ===

YES, you do, IF the transaction is non-recourse. The Bitcoin reference software does not display transactions as confirmed until six blocks have passed (confirmations). As transactions are buried in the chain they become increasingly non-reversible but are very reversible before the first confirmation. Two to six confirmations are recommended for non-recourse situations depending on the value of the transactions involved.

When people ask this question they are usually thinking about applications like supermarkets. This generally is a recourse situation: if somebody tries to double-spend on a face-to-face transaction it might work a few times, but probabalistically speaking eventually one of the double-spends will get noticed, and the penalty for shoplifting charges in most localities is calibrated to be several times worse than the proceeds of a single shoplifting event.

Double-spends might be a concern for something like a snack machine in a low-traffic area with no nearby security cameras. Such a machine shouldn't honor zero-confirmation payments, and should instead use some other mechanism of clearing Bitcoin or validating transactions against reversal, see the wiki article [[Myths#Point_of_sale_with_bitcoins_isn.27t_possible_because_of_the_10_minute_wait_for_confirmation|here]] for alternatives.

Applications that require immediate payment processing, like supermarkets or snack machines, need to manage the risks. Here is one way to reverse an unconfirmed payment:

A [[Double-spending#Finney_attack|Finney attack]] is where an attacker mines a block containing a movement of some coins back to themselves. Once they find a block solution, they quickly go to a merchant and make a purchase, then broadcast the block, thus taking back the coins. This attack is a risk primarily for goods that are dispatched immediately, like song downloads or currency trades. Because the attacker can't choose the time of the attack, it isn't a risk for merchants such as supermarkets where you can't choose exactly when to pay (due to queues, etc). The attack can fail if somebody else finds a block containing the purchasing transaction before you release your own block, therefore, merchants can reduce but not eliminate the risk by making purchasers wait some length of time that's less than a confirm.

Because pulling off this attack is not trivial, merchants who need to sell things automatically and instantly are most likely to adjust the price to include the cost of reversal fraud, or elect to use special insurance.

=== I was sent some bitcoins and they haven't arrived yet! Where are they? ===

Don't panic! There are a number of reasons why your bitcoins might not show up yet, and a number of ways to diagnose them.

The latest version of the Bitcoin-Qt client tells you how far it has yet to go in downloading the blockchain. Hover over the icon in the bottom right corner of the client to learn your client's status.

If it has not caught up then it's possible that your transaction hasn't been included in a block yet.

You can check pending transactions in the network by going [https://www.biteasy.com here] or [http://blockchain.info here] and then searching for your address. If the transaction is listed here then it's a matter of waiting until it gets included in a block before it will show in your client.

If the transaction is based on a coin that was in a recent transaction then it could be considered a low priority transaction. Transfers can take longer if the transaction fee paid was not high enough. If there is no fee at all the transfer can get a very low priority and take hours or even days to be included in a block.

=== Why does my Bitcoin address keep changing? ===
{{seealso|Address reuse}}
Unlike postal and email addresses, Bitcoin addresses are designed to be used exactly once only, for a single transaction.
Originally, wallets would display only a single address at a time, and change it when a transaction was received, but an increasing number of wallet implementations now generate an address when you explicitly want to receive a payment.

While it is technically possible to use an address for an arbitrary number of payments, this works by accident and harms both yourself ''and other unrelated third parties'', so it is considered a bad practice.
The most important concerns with such misuse involve loss of privacy and security:
both can be put into jeopardy when addresses are used for more than a single transaction only.

===How much will the transaction fee be?===

Some transactions might require a [[transaction fee]] for them to get confirmed in a timely manner. The transaction fee is processed by and received by the bitcoin miner. The most recent version of the Bitcoin client will estimate an appropriate fee when a fee might be required.

The fee is added to the payment amount. For example, if you are sending a 1.234 BTC payment and the client requires a 0.0005 BTC fee, then 1.2345 BTC will be subtracted from the wallet balance for the entire transaction and the address for where the payment was sent will receive a payment of 1.234 BTC.

A fee might be imposed because your transaction looks like a denial of service attack to the Bitcoin system. For example, it might be burdensome to transmit or it might recycle Bitcoins you recently received. The wallet software attempts to avoid generating burdensome transactions, but it isn't always able to do so: The funds in your wallet might be new or composed of many tiny payments.

Because the fee is related to the amount of data that makes up the transaction and not to the amount of Bitcoins being sent, the fee may seem extremely low (0.0005 BTC for a 1,000 BTC transfer) or unfairly high (0.004 BTC for a 0.02 BTC payment, or about 20%). If you are receiving tiny amounts (''e.g.'' as small payments from a mining pool) then fees when sending will be higher than if your activity follows the pattern of conventional consumer or business transactions.

As of Bitcoin 0.5.3 the required fee will not be higher than 0.05 BTC. For most users there is usually no required fee at all. If a fee is required it will most commonly be 0.0005 BTC.

=== What happens when someone sends me a bitcoin but my computer is powered off? ===

Bitcoins are not actually "sent" to your wallet; the software only uses that term so that we can use the currency without having to learn new concepts. Your wallet is only needed when you wish to spend coins that you've received.

If you are sent coins when your wallet client program is not running, and you later launch the wallet client program, the coins will eventually appear as if they were just received in the wallet. That is to say, when the client program is started it must download blocks and catch up with any transactions it did not already know about.

=== How long does "synchronizing" take when the Bitcoin client is first installed? What's it doing? ===

The popular Bitcoin client software from bitcoin.org implements a "full" Bitcoin node: It can carry out all the duties of the Bitcoin P2P system, it isn't simply a "client". One of the principles behind the operation of full Bitcoin nodes is that they don't assume that the other participants have followed the rules of the Bitcoin system. During synchronization, the software is processing historical Bitcoin transactions and making sure for itself that all of the rules of the system have been correctly followed.

In normal operation, after synchronizing, the software should use a hardly noticeable amount of your computer's resources.

When the wallet client program is first installed, its initial validation requires a lot of work from your computer's hard disk, so the amount of time to synchronize depends on your disk speed and, to a lesser extent, your CPU speed. It can take anywhere from a few hours to a day or so. On a slow computer it could take more than 40 hours of continuous synchronization, so check your computer's power-saving settings to ensure that it does not turn its hard disk off when unattended for a few hours. You can use the Bitcoin software during synchronization, but you may not see recent payments to you until the client program has caught up to the point where those transactions happened.

If you feel that this process takes too long, you can download a pre-synchronized blockchain from [http://eu2.bitcoincharts.com/blockchain/ http://eu2.bitcoincharts.com/blockchain/]. Alternatively, you can try an alternative "lite" client such as Multibit or a super-light client like electrum, though these clients have somewhat weaker security, are less mature, and don't contribute to the health of the P2P network.

==Networking==
=== Do I need to configure my firewall to run Bitcoin? ===

Bitcoin will connect to other nodes, usually on TCP port 8333. You will need to allow outgoing TCP connections to port 8333 if you want to allow your Bitcoin client to connect to many nodes. [[Testnet]] uses TCP port 18333 instead of 8333.

If you want to restrict your firewall rules to a few IPs, you can find stable nodes in the [[Fallback Nodes|fallback nodes list]].

=== How does the peer finding mechanism work? ===

Bitcoin finds peers primarily by forwarding peer announcements within its own network and each node saves a database of peers that it's aware of, for future use. In order to bootstrap this process Bitcoin needs a list of initial peers, these can be provided manually but normally it obtains them by querying a set of DNS domain names which have automatically updated lists, if that doesn't work it falls back to a built-in list which is updated from time to time in new versions of the software. In the reference software initial peers can also be specified manually by adding an addr.txt to the data directory or via the addnode parameter.

==Mining==
===What is mining?===
[[Mining]] is the process of spending computation power to secure Bitcoin transactions against reversal and introducing new Bitcoins to the system<ref>[https://www.bitcoinmining.com Bitcoin Mining]</ref>.

Technically speaking, mining is the calculation of a [[hash]] of the a block header, which includes among other things a reference to the previous block, a hash of a set of transactions and a [[nonce]]. If the hash value is found to be less than the current [[target]] (which is inversely proportional to the [[difficulty]]), a new block is formed and the miner gets the newly generated Bitcoins (25 per block at current levels). If the hash is not less than the current target, a new nonce is tried, and a new hash is calculated. This is done millions of times per second by each miner.

===Is mining used for some useful computation?===
The computations done when mining are internal to Bitcoin and not related to any other distributed computing projects. They serve the purpose of securing the Bitcoin network, which is useful.

===Is it not a waste of energy?===
Spending energy on creating and securing a free monetary system is hardly a waste. Also, services necessary for the operation of currently widespread monetary systems, such as banks and credit card companies, also spend energy, arguably more than Bitcoin would.

===Why don't we use calculations that are also useful for some other purpose?===
To provide security for the Bitcoin network, the calculations involved need to have some [http://bitcoin.stackexchange.com/questions/5617/why-are-bitcoin-calculation-useless/5618#5618 very specific features]. These features are incompatible with leveraging the computation for other purposes.

===How can we stop miners from creating zero transaction blocks?===
The incentive for miners to include transactions is in the fees that come along with them. If we were to implement some minimum number of transactions per block it would be trivial for a miner to create and include transactions merely to surpass that threshold. As the network matures, the block reward drops, and miners become more dependent on transactions fees to pay their costs, the problem of zero transaction blocks should diminish over time.

===How does the proof-of-work system help secure Bitcoin?===
Bitcoin uses the [[Hashcash]] proof of work with a minor adaption. To give a general idea of the mining process, imagine this setup:

payload = <some data related to things happening on the Bitcoin network>
nonce = 1
hash = [http://en.wikipedia.org/wiki/SHA2 SHA2]( [http://en.wikipedia.org/wiki/SHA2 SHA2]( payload + nonce ) )

The work performed by a miner consists of repeatedly increasing "nonce" until
the hash function yields a value, that has the rare property of being below a certain
target threshold. (In other words: The hash "starts with a certain number of zeroes",
if you display it in the fixed-length representation, that is typically used.)

As can be seen, the mining process doesn't compute anything special. It merely
tries to find a number (also referred to as nonce) which - in combination with the payload -
results in a hash with special properties.

The advantage of using such a mechanism consists of the fact, that it is very easy to check a result: Given the payload and a specific nonce, only a single call of the hashing function is needed to verify that the hash has the required properties. Since there is no known way to find these hashes other than brute force, this can be used as a "proof of work" that someone invested a lot of computing power to find the correct nonce for this payload.

This feature is then used in the Bitcoin network to secure various aspects. An attacker
that wants to introduce malicious payload data into the network, will need to do the
required proof of work before it will be accepted. And as long as honest miners have more
computing power, they can always outpace an attacker.

Also see [http://en.wikipedia.org/wiki/Hashcash Hashcash] and [http://en.wikipedia.org/wiki/Proof-of-work_system Proof-of-work system] and [http://en.wikipedia.org/wiki/SHA2 SHA2] and on Wikipedia.

===Why was the "Generate coin" option of the client software removed?===

The option wasn't removed, but it is now only accessible via the command-line or the configuration file. The reason for this is that many users were complaining after they turned on and expecting to receive coins. Without specialized mining hardware a user is exceptionally unlikely generate a block on their own at the network's current [[difficulty|security level]].

==Security==

===Could miners collude to give themselves money or to fundamentally change the nature of Bitcoin?===

There are two questions in here. Let's look at them separately.

;Could miners gang up and give themselves money?

Mining itself is the process of creating new blocks in the block chain. Each block contains a list of all the transactions that have taken place across the entire Bitcoin network since the last block was created, as well as a hash of the previous block. New blocks are 'mined', or rather, generated, by Bitcoin clients correctly guessing sequences of characters in codes called 'hashes,' which are created using information from previous blocks. Bitcoin users may download specialized 'mining' software, which allows them to dedicate some amount of their processing power – however large or small – to guessing at strings within the hash of the previous block. Whoever makes the right guess first, thus creating a new block, receives a reward in Bitcoins.

The block chain is one of the two structures that makes Bitcoin secure, the other being the public-key encryption system on which Bitcoin trade is based. The block chain assures that not only is every single transaction that ever takes place recorded, but that every single transaction is recorded on the computer of anyone who chooses to store the relevant information. Many, many users have complete records of every transaction in Bitcoins history readily available to them at any point, and anyone who wants in the information can obtain it with ease. These things make Bitcoin very hard to fool.

The Bitcoin network takes considerable processing power to run, and since those with the most processing power can make the most guesses, those who put the most power toward to sustaining the network earn the most currency. Each correct guess yields, at present, twenty-five Bitcoins, and as Bitcoins are presently worth something (although the value still fluctuates) every miner who earns any number of Bitcoins makes money. Some miners pull in Bitcoins on their own; and some also join or form pools wherein all who contribute earn a share of the profits.

Therefore, first answer is a vehement “yes” – not only can miners collude to get more money, Bitcoin is designed to encourage them to do so. Bitcoin pools are communal affairs, and there is nothing dishonest or underhanded about them.

Of course, the real question is:

;Can they do so in ways not sanctioned by Bitcoin network? Is there any way to rip off the network and make loads of money dishonestly?

Bitcoin isn't infallible. It can be cheated, but doing so is extremely difficult. Bitcoin was designed to evade some of the central problems with modern currencies – namely, that their trustworthiness hinges upon that of people who might not have users' best interests in mind. Every currency in the world (other than Bitcoin) is controlled by large institutions who keep track of what's done with it, and who can manipulate its value. And every other currency has value because people trust the institutions that control them.

Bitcoin doesn't ask that its users trust any institution. Its security is based on the cryptography that is an integral part of its structure, and that is readily available for any and all to see. Instead of one entity keeping track of transactions, the entire network does, so Bitcoins are astoundingly difficult to steal, or double-spend. Bitcoins are created in a regular and predictable fashion, and by many different users, so no one can decide to make a whole lot more and lessen their value. In short, Bitcoin is designed to be inflation-proof, double-spend-proof and completely distributed.

Nonetheless, there are a few ways that one can acquire Bitcoins dishonestly. Firstly, one can steal private keys. Key theft isn't something that Bitcoin security has been designed to prevent: it's up to users to keep their keys safe. But the cryptography is designed so that it is completely impossible to deduce someone's private key from their public one. As long as you keep your private key to yourself, you don't have much to worry about. Furthermore, one could theoretically create a new block chain, but due to the way in which the block chain is constructed, this would be extremely difficult and require massive amounts of processing power. A full explanation of the difficulties involved can be found in the [[block chain]] article.

Bitcoin can be ripped off – but doing so would be extremely hard and require considerable expertise and a staggering amount of processing power. And it's only going to get harder with time. Bitcoin isn't impenetrable, but it's close enough to put any real worries in the peripherals.

;Could miners fundamentally change the nature of Bitcoin?

Once again, almost certainly not.

Bitcoin is a distributed network, so any changes implemented to the system must be accepted by all users. Someone trying to change the way Bitcoins are generated would have to convince every user to download and use their software – so the only changes that would go through are those that would be equally benefit all users.

And thus, it is more or less impossible for anyone to change the function of Bitcoin to their advantage. If users don't like the changes, they won't adopt them, whereas if users do like them, then these will help everyone equally. Of course, one can conceive of a situation where someone manages to get a change pushed through that provides them with an advantage that no one notices, but given that Bitcoin is structurally relatively simple, it is unlikely that any major changes will go through without someone noticing first.

The fact that such changes are so difficult to make testifies to the fully distributed nature of Bitcoin. Any centrally controlled currency can be modified by its central agency without the consent of its adherents. Bitcoin has no central authority, so it changes only at the behest of the whole community. Bitcoins development represents a kind of collective evolution; the first of its kind among currencies.

==Help==
===I'd like to learn more. Where can I get help?===

* Read the [[Introduction|introduction to bitcoin]]
* See the videos, podcasts, and blog posts from the [[Press]]
* Read and post on the [[:Bitcoin Wiki:Community_portal#Bitcoin_Community_Forums|forums]]
* Chat on one of the [[:Bitcoin Wiki:Community_portal#IRC_Chat|Bitcoin IRC]] channels
* Listen to [http://omegataupodcast.net/2011/03/59-bitcoin-a-digital-decentralized-currency/ this podcast], which goes into the details of how bitcoin works
* Ask questions on the [http://bitcoin.stackexchange.com Bitcoin Stack Exchange]
* Use [http://bitcoinx.io BitcoinX.io] to help beginners learn about reputable Bitcoin exchanges and Bitcoin wallets

==See Also==

* [[Man page]]
* [[Introduction]]

==References==
<references>
<references/>
{{Reflist|2}}

[[de:FAQ]]
[[zh-cn:FAQ]]
[[fr:FAQ]]
[[ru:FAQ]]

[[Category:Technical]]
[[Category:Vocabulary]]

Using Bitcoin

2015-07-07T15:33:10Z

Sunnankar: /* See also */

<div style="background:#dddddd;border:solid gray 1px;width:70%;margin:auto;">
Current releases of the bitcoin client have a different user interface than the versions used in this article.

This article could use an update. See the discussion for this article for more.
</div>

This page is a detailed tutorial to help new users understand and using bitcoin. After you read this page, you'll know the basics of what bitcoin is and how it is structured, how to get and install the bitcoin client, where to get coins, and how to use the client to send and receive transactions.

If you want to ignore all the details of how the system works, and just want to start using it, see the [[Getting started]] page instead.

=What is Bitcoin=

Bitcoin is a distributed [[digital currency]] based on strong cryptographic principles. Each coin is assigned to the owner's public key, and is transferrable via cryptographically signed messages.

=Getting started=

In this section, you'll learn where to get the client, how to install it on different operating systems, and download the [[block chain]].

==Download and install the client==

First, download the bitcoin client from http://bitcoin.org/. Choose the appropriate link depending on your operating system, and install in the usual manner. For Windows, easiest is probably the executable installer. For Linux, note that the tar.gz contains the binary build, in addition to the source, so if you run a recent distribution, you should be able to just run the binary without compiling yourself.

===Issues with Linux package repositories===
Be warned that the version of Bitcoin Core in some package repositories are severely out of date and may be harmful to use. For Debian, users should use [https://packages.debian.org/source/unstable/bitcoin the package from the 'unstable' repository]. For Ubuntu and derivatives, please use the PPA link [https://bitcoin.org/en/download on bitcoin.org]. Please see [https://launchpad.net/+help-soyuz/ppa-sources-list.html this guide] for details on how to use the PPA. You can also choose to use the static binary or to compile from source (both are in the 'tgz' file on the bitcoin.org download page), although updates will not be automated. Please refer to [https://bitcoin.org/en/download this page] for the latest version number.

==Starting the client and connecting to the network==

[[File:First time run fin.png|400px|thumb|right|Bitcoin is initializing by establishing a connection to other clients and downloading the blocks.]]
Bitcoin comes with a GUI client called "bitcoin", and a CLI (text-mode) client called "bitcoind". It is probably more user-friendly to start with the GUI, so launch the bitcoin client.

When you start for the first time, your bitcoin wallet will be created automatically, and the client will attempt to establish connections to other nodes on the network and start downloading the bitcoin [[block chain]]. You must get all of the blocks in the chain before sending/receiving transactions. [http://blockexplorer.com/q/getblockcount Click here] to see the current number of blocks in the chain. This download may take as long as several hours.

==Client features==

Your starting bitcoin address (you can have as many as you want - we'll talk about [[#Bitcoin addresses|addresses]] later) shows in a text box at the top. Right below it is your total bitcoin balance, which, of course, to start with will be zero. There is a list box below it showing all your transactions, which can be variously filtered with tabs, which again will be empty to start with.

The status bar at the bottom will display some important information. If you have [[#Generating bitcoins|bitcoin generation (block hashing)]] turned on, on the left the client will display your hash rate. To the right of that, you will see the number of bitcoin nodes your client is connected to, then, the number of blocks your client has in its chain, and finally, the number of transactions you have in your wallet.

=Using bitcoin=

In this section you will learn about bitcoin addresses, sending and receiving transactions, the block chain and transaction confirmations, where to get your first bitcoins (faucet), generation. Tips on keeping wallet safe.

==Getting your first bitcoins==

There are few things more exciting than getting your first bitcoins! So once you have all the blocks downloaded, head on over to the [https://freebitcoins.appspot.com/ bitcoin faucet], fill out the form and put in your bitcoin address, and receive some free bitcoin! (You can do this before finishing the block chain download, but you won't see the coins in your wallet until you finish downloading the blocks... which would put a damper on the whole excitement bit.)

See [http://en.bitcoin.it/wiki/Trade#Samples_and_Marketing_Offers Samples and Marketing Offers] for other free bitcoins and marketing offers.

Once you submit the form successfully, you should see a new transaction in your client within seconds. But it will be grayed out, and have 0/unconfirmed status:
[[File:First btc recv.png|frame|none]]

Once your transaction makes it into the block chain, the confirmation count will grow in step with the number of blocks in the chain. By default, the client stops showing "unconfirmed" after the transaction is 6 blocks deep in the chain:
[[File:Six confirms bitcoin client.png|frame|none]]

==Bitcoin addresses==

You can create as many new addresses as you like. Using a different address each time helps to preserve your [[anonymity]].

You cannot send BTC to an invalid address. Client will refuse to send payment to a misspecified address. (Though with care you can craft a valid but nonexistent address.)




==Generating bitcoins==

In order to generate bitcoins, you will need to perform bitcoin [[mining]]. As of 2013, the competition for bitcoin mining has become intense, so you are unlikely to achieve much without specialized hardware.

=See also=

* [[Getting started]] A brief tutorial for the impatient
* [http://bitcoinX.io BitcoinX.io] View where to buy and store your bitcoins on the only Bitcoin peer-to-peer review site, BitcoinX
* [https://www.weusecoins.com What Is Bitcoin?]
* [https://www.bitcoinmining.com What Is Bitcoin Mining?]

[[Category:Introduction]]

Help:Introduction

2015-07-07T15:31:43Z

Sunnankar: /* See Also */

The purpose of this page is to provide a general overview of the Bitcoin system and economy.

==Basic Concepts==

===Currency===

Alice wants to buy the [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks] which Bob has for sale. In return, she must provide something of equal value to Bob. The most efficient way to do this is by using a medium of exchange that Bob accepts which would be classified as currency. Currency makes trade easier by eliminating the need for [http://en.wikipedia.org/wiki/Coincidence_of_wants coincidence of wants] required in other systems of trade such as barter. Currency adoption and acceptance can be global, national, or in some cases local or community-based.

===Banks===

Alice need not provide currency to Bob in-person. She may instead transfer this value by first entrusting her currency to a bank who promises to store and protect Alice's currency notes. The bank gives Alice a written promise (called a "bank statement") that entitles her to withdraw the same number of currency bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of passing on the currency bills to Bob on her behalf. This is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount the next time he checks his balance or receives his bank statement.

Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers that do the job of interacting with customers instead of paid bank employees. The task of these machines is to learn what each customer wants to do with their money and, to the extent that it is possible, act on what the customer wants (for example, ATMs can hand out cash). Customers can always know how much money they have in their accounts, and they are confident that the numbers they see in their bank statements and on their computer screens accurately reflect the number of dollars that they can get from the bank on demand. They can be so sure of this that they can accept those numbers in the same way they accept paper banknotes (this is similar to the way people started accepting paper dollars when they had been accepting gold or silver).

Such a system has several disadvantages:
* It is costly. [https://en.wikipedia.org/wiki/Electronic_funds_transfer EFTs] in Europe can cost 25 euros. Credit transactions can cost several percent of the transaction.
* It is slow. Checking and low cost wire services take days to complete.
* In most cases, it cannot be anonymous.
* Accounts can be frozen, or their balance partially or wholly confiscated.
* Banks and other payment processors like PayPal, Visa, and Mastercard may refuse to process payments for certain legal entities.

Bitcoin is a system of owning and voluntarily transferring amounts of so-called ''bitcoins'', in a manner similar to an on-line banking, but pseudonymously and without reliance on a central authority to maintain account balances. If bitcoins are valuable, it is because they are useful and limited in supply.

==Bitcoin Basics==

===Creation of coins===

The creation of coins must be limited for the currency to have any value.

New coins are slowly [[Mining|mined]] into existence by following a mutually agreed-upon set of rules. A user [[Mining|mining]] bitcoins is running a software program that searches for a solution to a very difficult math problem the difficulty of which is precisely known. This difficulty is automatically adjusted on a predictable schedule so that the number of solutions found globally for a given unit of time is constant: the global system aims for 6 per hour. When a solution is found, the user may tell everyone of the existence of this newly found solution along with other information packaged together in what is called a "[[Block|block]]". The solution itself is a [[Proof of work| proof-of-work]] or PoW. It is hard to find, but easy to verify.

Blocks create 25 new bitcoins at present. This amount, known as the block reward, is an incentive for people to perform the computation work required for generating blocks. Roughly every 4 years, the number of bitcoins that can be "mined" in a block reduces by 50%. Originally the block reward was 50 bitcoins; it halved in November 2012. Any block that is created by a malicious user that does not follow this rule (or any other rules) will be rejected by everyone else. In the end, no more than 21 million bitcoins will ever exist.

Because the block reward will decrease over the long term, miners will some day instead pay for their hardware and electricity costs by collecting [[Transaction_fee|transaction fees]]. The sender of money may voluntarily pay a small transaction fee which will be kept by whoever finds the next block. Paying this fee will encourage miners to include the transaction in a block more quickly.

===Sending payments===

To guarantee that a third-party, let's call her Eve, cannot spend other people's bitcoins by creating transactions in their names, Bitcoin uses [[Wikipedia:Public-key_cryptography|public key cryptography]] to make and verify digital signatures. In this system, each person, such as Alice or Bob, has one or more addresses each with an associated pair of public and private keys that they may hold in a [[Wallet|wallet]]. Only the user with the private key can sign a transaction to give some of their bitcoins to somebody else, but anyone can validate the signature using that user’s public key.

Suppose Alice wants to send a bitcoin to Bob.
* Bob sends his address to Alice.
* Alice adds Bob’s address and the amount of bitcoins to transfer to a message: a 'transaction' message.
* Alice signs the transaction with her private key, and announces her public key for signature verification.
* Alice broadcasts the transaction on the Bitcoin network for all to see.

(Only the first two steps require human action. The rest is done by the Bitcoin client software.)

Looking at this transaction from the outside, anyone who knows that these addresses belong to Alice and Bob can see that Alice has agreed to transfer the amount to Bob, because nobody else has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her control.

Later on, when Bob wishes to transfer the same bitcoins to Charley, he will do the same thing:
* Charlie sends Bob his address.
* Bob adds Charlie's address and the amount of bitcoins to transfer to a message: a 'transaction' message.
* Bob signs the transaction with his private key, and announces his public key for signature verification.
* Bob broadcasts the transaction on the Bitcoin network for all to see.

Only Bob can do this because only he has the private key that can create a valid signature for the transaction.

Eve cannot change whose coins these are by replacing Bob’s address with her address, because Alice signed the transfer to Bob using her own private key, which is kept secret from Eve, and instructing that the coins which were hers now belong to Bob. So if Charlie accepts that the original coin was in the hands of Alice, he will also accept the fact that this coin was later passed to Bob, and now Bob is passing this same coin to him.

===Preventing [[double-spending]]===

The process described above does not prevent Alice from using the same bitcoins in more than one transaction. The following process does; this is the primary innovation behind Bitcoin.

* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).
* To be accepted in the chain, transaction blocks must be valid and must include [[proof of work]] (one block generated by the network every 10 minutes).
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.
* When multiple valid continuations to this chain appear, only the longest such branch is accepted and it is then extended further.

When Bob sees that his transaction has been included in a block, which has been made part of the single longest and fastest-growing block chain (extended with significant computational effort), he can be confident that the transaction by Alice has been accepted by the computers in the network and is permanently recorded, preventing Alice from creating a second transaction with the same coin. In order for Alice to thwart this system and double-spend her coins, she would need to muster more computing power than all other Bitcoin users combined.

===Anonymity===

When it comes to the Bitcoin network itself, there are no "accounts" to set up, and no e-mail addresses, user-names or passwords are required to hold or spend bitcoins. Each balance is simply associated with an address and its public-private key pair. The money "belongs" to anyone who has the private key and can sign transactions with it. Moreover, those keys do not have to be registered anywhere in advance, as they are only used when required for a transaction. Transacting parties do not need to know each other's identity in the same way that a store owner does not know a cash-paying customer's name.

A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:

:1PHYrmdJ22MKbJevpb3MBNpVckjZHt89hz

Each person can have many such addresses, each with its own balance, which makes it very difficult to know which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can generate a new public-private key pair for each individual receiving transaction and the Bitcoin software encourages this behavior by default. Continuing the example from above, when Charlie receives the bitcoins from Bob, Charlie will not be able to identify who owned the bitcoins before Bob.

===Capitalization / Nomenclature===

Since Bitcoin is both a currency and a protocol, capitalization can be confusing. Accepted practice is to use ''Bitcoin'' (singular with an upper case letter B) to label the protocol, software, and community, and ''bitcoins'' (with a lower case b) to label units of the currency.

==Where to see and explore==

You can directly explore the system in action by visiting [https://www.biteasy.com/ Biteasy.com], [http://blockchain.info/ Blockchain.info], [http://btc.blockr.io/ Blokr.io Bitcoin Block Explorer] or [http://blockexplorer.com/ Bitcoin Block Explorer].
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.
Note how many blocks were generated in the last hour, which on average will be 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K).
This should give you an indication of how active the system is.

Next, navigate to one of these blocks.
The block's [[hash]] begins with a run of zeros. This is what made creating the block so difficult; a hash that begins with many zeros is much more difficult to find than a hash with few or no zeros. The computer that generated this block had to try many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.
Next, see the line titled ''Previous block''. Each block contains the hash of the block that came before it. This is what forms the chain of blocks.
Now take a look at all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of "thin air" and possibly a fee collected from other transactions in the same block.

Drill down into any of the transactions and you will see how it is made up of one or more amounts coming in and out.
Having more than one incoming and outgoing amount in a transaction enables the system to join and break amounts in any possible way, allowing for any fractional amount needed. Each incoming amount is a past transaction (which you can also view) from someone's address, and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also navigate down into if it has already taken place.)

Finally you can follow any of the [[Address|addresses]] links and see what public information is available for them.

To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Monitor]] and [[Bitcoin Watch]]. The first shows a real-time visualization of events on the Bitcoin network, and the second lists general statistics on the amount and size of recent transactions.

===How many people use Bitcoin?===

This is quite a difficult question to answer accurately. One approach is to count how many bitcoin clients connected to the network in the last 24 hours. We can do this because some clients transmit their addresses to the other members of the network periodically. In September 2011 this method suggested that there were about {{formatnum:60000}} users.

In October 2014, according to [http://www.coindesk.com/state-of-bitcoin-q3-2014-report-maturing-ecosystem-price-pressure/ Coindesk report] there were more than 7.5 million bitcoin wallets.

==See Also==
* [http://bitcoinhelp.net Bitcoin Help] — the simple guide to Bitcoin.
* Learn the entire history of Bitcoin in the interactive timeline at [http://historyofbitcoin.org History of Bitcoin].
* [https://www.weusecoins.com What Is Bitcoin?]
* [https://www.bitcoinmining.com What Is Bitcoin Mining?]

[[zh-cn:简介]]

[[de:Einführung]]
[[fr:Introduction]]

Category:History

2015-07-05T14:39:43Z

Sunnankar: /* 2011 */

{{outdated}}
Two fantastic compilations of Bitcoin history are available at the [http://historyofbitcoin.org HistoryOfBitcoin.org] and [http://igotbitcoin.com/milestones igotbitcoin.com/milestones] sites.

== Important milestones of the Bitcoin project ==
=== 2008 ===
{| style="text-align: left"
|-
! width="8em" | August 18
|| Domain name "bitcoin.org" registered<ref>[https://bitcointalk.org/index.php?topic=103369.msg1135218#msg1135218 According to theymos], Satoshi registered bitcoin.org via https://www.anonymousspeech.com/ which allows to anonymously register domains.</ref>.
|-
! October 31
|| [http://article.gmane.org/gmane.comp.encryption.general/12588/ Bitcoin design paper] published
|-
! November 09
|| Bitcoin project registered at SourceForge.net
|}

=== 2009 ===
{| style="text-align: left"
|-
! width="8em" | January 3
|| [http://www.BlockExplorer.com/b/0 Genesis block] established at 18:15:05 GMT
|-
! January 9
|| Bitcoin v0.1 released and announced on the [http://www.mail-archive.com/cryptography@metzdowd.com/msg10152.html cryptography mailing list]
|-
! January 12
|| First Bitcoin transaction, [http://www.BlockExplorer.com/b/170 in block 170] - from [[Satoshi]] to Hal Finney<ref>[http://bitcointalk.org/index.php?topic=91806.msg1012234#msg1012234 Earliest Block With A Spend]</ref>.
|-
! October 5
|| Exchange rates [http://newlibertystandard.wikifoundry.com/page/2009+Exchange+Rate published] by New Liberty Standard. $1 = 1,309.03 BTC (and [[User:theymos|theymos]] thought NLS was overcharging<ref>[http://bitcointalk.org/index.php?topic=104287.msg1143955#msg1143955 Historical Price Data for 2009]</ref>)
|-
! October 9
|| #bitcoin-dev channel registered on freenode IRC.
|-
! December 16
|| Bitcoin v0.2 released
|-
! December 30
|| First difficulty increase at 06:11:04 GMT
|}

=== 2010 ===
{| style="text-align: left"
|-
! width="8em" | February 6
|| [[Bitcoin Market]] established
|-
! May 22
|| laszlo first to buy pizza with Bitcoins agreeing upon paying 10,000 BTC for ~$25 worth of pizza courtesy of jercos<ref>[https://bitcointalk.org/index.php?topic=137.msg1195#msg1195 bitcointalk post] where laszlo confirmed having bought pizza</ref>
|-
! July 7
|| Bitcoin v0.3 released
|-
! July 11
|| Bitcoin v0.3 release mentioned on slashdot<ref>[http://news.slashdot.org/story/10/07/11/1747245/Bitcoin-Releases-Version-03 slashdot] metiones Bitcoin</ref>, bringing a large influx of new bitcoin users.
|-
! July 12
|| Beginning of a 10x increase in exchange value over a 5 day period, from about $0.008/BTC to $0.08/BTC
|-
! July 17
|| [[MtGox]] established
|-
! July 18
|| ArtForz generated his first block after establishing his personal OpenCL GPU hash farm
|-
! August 15
|| Bug in the bitcoin code allows a bad transaction into block 74638. Users quickly adopt fixed code and the "good" block chain overtook the bad one at a block height of 74691, 53 blocks later ([[Incidents#Value_overflow]]).
|-
! September 14
|| jgarzik [https://bitcointalk.org/index.php?topic=133.msg12921#msg12921 offered] 10,000 BTC (valued at ~$600-650) to puddinpop to open source their windows-based CUDA client
|-
! September 14
|| Block [http://blockexplorer.com/b/79764 79,764] is first to be mined using split allocation of the generation reward.
|-
! September 18
|| puddinpop [https://bitcointalk.org/index.php?topic=133.msg13135#msg13135 released] source to their windows-based CUDA client under MIT license
|-
! September 29
|| kermit [https://bitcointalk.org/index.php?topic=1306.0 discovered] a microtransactions exploit which precipitated the Bitcoin v0.3.13 release
|-
! October 01
|| [https://bitcointalk.org/?topic=1334.0 First public OpenCL miner] released
|-
! October 04
|| Original Bitcoin History wiki page (this page) established (ooh so meta) on Bitcoin.org's wiki.
|-
! October 07
|| Exchange rate started climbing up from $0.06/BTC after several flat months.
|-
! October 16
|| First recorded escrowed bitcoin trade conducted, between nanotube and Diablo-D3, escrowed by theymos.
|-
! October 17
|| [[Bitcoin_OTC|#bitcoin-otc]] trading channel established on freenode IRC.
|-
! October 28
|| First bitcoin short sale transaction initiated, with a loan of 100 BTC by nanotube to [[User:Kiba|kiba]], facilitated by the [[Bitcoin-otc|#bitcoin-otc]] market.
|-
! November 6
|| The [https://bitcointalk.org/index.php?topic=1672 Bitcoin economy passed US $1 million]. The MtGox price touched USD $0.50/BTC.
|-
! December 7
|| Bitcoind was compiled for the Nokia N900 mobile computer by doublec. The following day, ribuck sent him 0.42 BTC in the first portable-to-portable Bitcoin transaction.
|-
! December 9
|| The generation difficulty passed 10,000.
|-
|
|| First bitcoin call option contract sold, from nanotube to [[User:Sgornick|sgornick]], via the [[Bitcoin-otc|#bitcoin-otc]] market.
|-
! December 16
|| [http://mining.bitcoin.cz/ Bitcoin Pooled Mining], operated by slush, found its first block
|}

=== 2011 ===
{| style="text-align: left"
|-
! width="8em" | January 2
|| [[Tonal Bitcoin]] units standardized.
|-
! January 8
|| [[History of Bitcoin]] page (this page) created after replicating from original Bitcoin History page on Bitcoin.org.
|-
|
|| Bitcoin Pooled Mining reached a total of 10,000 Mhash/s
|-
! January 27
|| Largest numeric value ever traded for bitcoins thus far occurred on this date. Three currency bills from Zimbabwe, known as Zimdollars, were traded on [[Bitcoin-otc|#bitcoin-otc]] at the rate of 4 BTC for each of the one-hundred trillion dollar ($100,000,000,000,000) Zimbabwe notes<ref>Serial numbers for Zimdollars sold: AA1669317, AA1669318 and AA1669319</ref>
|-
! January 28
|| Block 105000 was generated. This means that 5.25 million bitcoins have been generated, which is just over one-quarter of the eventual total of nearly 21 million.
|-
! February 9
|| Bitcoin reached parity with the US dollar, touching $1 per BTC at [[MtGox]].
|-
! February 10
|| Bitcoin.org website struggles to handle [https://bitcointalk.org/index.php?topic=3444.0 traffic] resulting from mentions on Slashdot<ref>[http://news.slashdot.org/story/11/02/10/189246/Online-Only-Currency-BitCoin-Reaches-Dollar-Parity Online-Only Currency BitCoin Reaches Dollar Parity]</ref>, Hacker News and Twitter following the news that parity had been reached.
|-
! February 14
|| A vehicle was, for the first time, offered in exchange for a certain number of bitcoins<ref>[https://bitcointalk.org/index.php?topic=3485.0 Car for Sale - Australia]</ref>.
|-
! March 1
|| [[MagicalTux]] buys mtgox.com from its founder [[Jed McCaleb]]
|-
! March 6
|| Total Bitcoin network computation speed for a short time reached a new high of almost 900Ghash/sec, dropping to 500Ghash/sec soon after. Some speculate that this was due to some supercomputer or bot-net that joined the network ([http://bitcoin.atspace.com/mysteryminer.html mystery miner]).
|-
! March 18
|| BTC/USD exchange rate reaches a 6-week low point at almost $0.70/BTC, after what appeared to be a short burst of, possibly automated, BTC sales at progressively lower prices. BTC price had been declining since the February 9 high.
|-
! March 22
|| [https://www.weusecoins.com/ WeUseCoins] releases the viral video [https://www.youtube.com/watch?v=Um63OQz3bjo What Is Bitcoin?] which has had more than 6.4 million views.
|-
! March 25
|| Difficulty decreased nearly 10%. A decrease has only occurred once before, and this decrease of nearly 10% was the largest.
|-
! March 27
|| The first market for exchanging bitcoins to and from the British Pound Sterling BTC/GBP, [[Britcoin]], opens.
|-
! March 31
|| The first market for exchanging bitcoins to and from Brazilian Reals, [[Bitcoin Brazil]], opens.
|-
! April 5
|| The first market for exchanging bitcoins to and from the Polish złoty, [[BitMarket.eu]], opens.
|-
! April 12
|| First bitcoin put option contract sold via the [[Bitcoin-otc|#bitcoin-otc]] market.
|-
! April 16
|| TIME does [http://techland.time.com/2011/04/16/online-cash-bitcoin-could-challenge-governments/ an article on Bitcoin].
|-
! April 23
|| BTC/USD exchange rate reaches and passes parity with the Euro (EUR) on [[MtGox]] exchange.
|-
|
|| BTC/USD exchange rate reaches and passes parity with the British Sterling Pound (GBP) on [[MtGox]] exchange.
|-
|
|| Value of the Bitcoin money stock at current exchange rate passes $10 million USD threshold.
|-
! April 27
|| [[VirWoX]] opens first market to trade bitcoins against a virtual currency on BTC/SL (Second Life Lindens) exchange.
|-
! April 30
|| The generation difficulty passed 100,000.
|-
! June 2
|| The exchange rate at [[MtGox]] touched 10 USD per BTC.
|-
! June 3
|| [[Tonal Bitcoin]] reached parity with the US cent, touching 1¢ per TBC at [[Bitcoin Market]].
|-
! June 8
|| The [[MtGox]] exchange rate peaked at 31.91 USD, at a "market capitalization" of about $206 M [http://bitcoin.stackexchange.com/questions/2047/market-capitalization-over-time].
|-
! June 12
|| The [[MtGox]] exchange rate briefly dropped to near 10 USD four days after the peak, in its largest percentage price retreat to date.
|-
! June 13
|| Forum user allinvain claimed to have had [http://forum.bitcoin.org/index.php?topic=16457.0 25,000 BTC stolen] from his Bitcoin wallet (approx. USD equivalent $375,000).
|-
! June 19
|| The MtGox database was compromised and the user table was leaked, containing details of 60,000 usernames, email addresses and password hashes, some of which were overly simple to brute force passwords.
|-
! June 19
|| Someone was able to access an admin account at MtGox and issue sell orders for hundreds of thousands of fake bitcoins, forcing the MtGox price down from $17.51 per bitcoin to $0.01. MtGox announced that these trades would be reversed. Trading was halted at MtGox for 7 days (and also briefly at TradeHill and Britcoin while their security was reviewed).
|-
! June 19
|| Some of the users on the leaked MtGox database had used the same username at MyBitcoin and had their passwords hacked. About 600 of them had their balance [http://forum.bitcoin.org/index.php?topic=22221.msg279396#msg279396 stolen from their MyBitcoin accounts]. One user lost over 2000 BTC.
|-
! June 20
|| The EFF announced that it was no longer accepting Bitcoin donations due to legal uncertainties.
|-
! June 24
|| The generation difficulty passed 1,000,000 with Block [http://blockexplorer.com/b/133056 133056].
|-
! July 19
|| "Let it go on record that at 4:05pm CET [19 July 2011], my manager Tadek was the first person in the world to receive [testnet] Bitcoins via NFC ;)" - Mike Hearn
|-
! July 22
|| [[BitCoins Mobile]], the first Bitcoin application for iPad was released by [http://www.intervex.net Intervex Digital].
|-
! July 26
|| [http://www.room77.de/ Room77] [https://bitcointalk.org/index.php?topic=32162.0 becomes] the first brick-and-mortar business (bar) to accept Bitcoin as a means of payment.
|-
! July 30
|| [http://pastebin.com/raw.php?i=BUB3dygQ Tribute to Len Sassaman] included in the blockchain<ref>[http://bitcointalk.org/index.php?topic=33618.msg420597#msg420597 A Tribute to Len "rabbi" Sassama]</ref>.
|-
! August 20
|| First Bitcoin Conference and World Expo held, in NYC.<ref>[http://bitcoinme.com/index.php/conference/ New York Conference 2011]</ref>
|-
! August 23
|| [[P2Pool]], the first P2P decentralized pool, mines its first Bitcoin mainnet block (Block [http://blockexplorer.com/b/142312 142,312]).
|-
! August 30
|| Difficulty adjustment at block [http://blockexplorer.com/b/143136 143,136] marks the first back-to-back drop.
|-
! November 15
|| First CVE (CVE-2011-4447) assigned to a Bitcoin client exploit.
|-
! November 25
|| First European Bitcoin Conference in Prague, Czech Rep.<ref>[http://bitgroups.org/ Prague Conference 2011]</ref>
|-
! December 12
|| Largest amount of fees, to-date, in a single transaction, and most fees in a single block. A [http://blockexplorer.com/tx/1d7749c65c90c32f5e2c036217a2574f3f4403da39174626b246eefa620b58d9 transaction] paid 171 BTC in fees in [http://blockexplorer.com/b/157235 block 157235]<ref>[http://bitcointalk.org/index.php?topic=88423.msg973509#msg973509 Largest fee ever?]</ref>.
|}

=== 2012 ===
{| style="text-align: left"
|-
! width="8em" | March 1
|| Largest theft of bitcoins to-date occurred (near 50K BTC) after security breach at web host Linode.
|-
! width="8em" | April 1
|| Pay-to-script-hash ([[P2SH]]) as defined through [[BIP 0016]] goes live.
|-
! May 08
|| A single service, [[Satoshi Dice]] becomes responsible for over half the transaction volume on the Bitcoin blockchain.
|-
! June 3
|| Largest block (most transactions), to-date (June 3), is [http://BlockExplorer.com/b/181919 block 181919] with 1322 transactions<ref>[http://bitcointalk.org/index.php?topic=85353.msg939859#msg939859 Largest block to date]</ref>.
|-
! July 22
|| One millionth topic reply was posted on the unofficial [[Bitcoin Forum]] <ref>[https://bitcointalk.org/index.php?topic=94608.0 Topic about one millionth forum post]</ref>.
|-
! September 15-16
|| Bitcoin Conference in London <ref>[http://bitcoin2012.com/ London Conference 2012]</ref>.
|-
! September 27
|| Formation of the [[Bitcoin Foundation]].
|-
! November 28
|| Halving day. [http://blockexplorer.com/b/210000 Block 210,000] is the first with a block reward subsidy of only 25 BTC.
|-
! December 6
|| First Bitcoin exchange [https://bitcointalk.org/index.php?topic=129461.0 licensed "as a bank" in europe] (actually a PSP which is like a bank, without debt-money issuing).
|}

=== 2013 ===
{| style="text-align: left"
|-
! width="8em" | February 19
|| Bitcoin Client v0.8 released featuring improved download speed and [https://en.wikipedia.org/wiki/Bloom_filter Bloom Filtering]
|-
! February 28
|| The [[MtGox]] exchange rate broke the June 8 2011 peak of 31.91 USD. The first all time high since 601 days
|-
! March 12
|| A previously undiscovered protocol rule results in a [http://bitcoin.org/chainfork.html hard fork of the 0.8.0 reference client].
|-
! March 18
|| The United States federal agency charged with enforcing laws against money laundering (FinCEN) declares that Bitcoin users are subject to regulation only at the point of USD-BTC exchange.<ref>[http://arstechnica.com/tech-policy/2013/03/us-regulator-bitcoin-exchanges-must-comply-with-money-laundering-laws/ US regulator: Bitcoin exchanges must comply with money-laundering laws]</ref>
|-
! March 28
|| Total Bitcoin market cap passes $1 billion. <ref>http://spectrum.ieee.org/computing/networks/bitcoin-hits-1billion</ref>
|-
! April 1
|| Bitcoin price breaks 100 USD on [[MtGox]] and other major exchanges.
|-
|}

==See Also==

* [[Bitcoin Firsts]]
* [[Press]]
* [https://bitcoinhelp.net/know/more/price-chart-history Bitcoin Price Chart with Historic Events]

==References==
<references />

Category:History

2015-07-05T14:39:12Z

Sunnankar: /* 2011 */

{{outdated}}
Two fantastic compilations of Bitcoin history are available at the [http://historyofbitcoin.org HistoryOfBitcoin.org] and [http://igotbitcoin.com/milestones igotbitcoin.com/milestones] sites.

== Important milestones of the Bitcoin project ==
=== 2008 ===
{| style="text-align: left"
|-
! width="8em" | August 18
|| Domain name "bitcoin.org" registered<ref>[https://bitcointalk.org/index.php?topic=103369.msg1135218#msg1135218 According to theymos], Satoshi registered bitcoin.org via https://www.anonymousspeech.com/ which allows to anonymously register domains.</ref>.
|-
! October 31
|| [http://article.gmane.org/gmane.comp.encryption.general/12588/ Bitcoin design paper] published
|-
! November 09
|| Bitcoin project registered at SourceForge.net
|}

=== 2009 ===
{| style="text-align: left"
|-
! width="8em" | January 3
|| [http://www.BlockExplorer.com/b/0 Genesis block] established at 18:15:05 GMT
|-
! January 9
|| Bitcoin v0.1 released and announced on the [http://www.mail-archive.com/cryptography@metzdowd.com/msg10152.html cryptography mailing list]
|-
! January 12
|| First Bitcoin transaction, [http://www.BlockExplorer.com/b/170 in block 170] - from [[Satoshi]] to Hal Finney<ref>[http://bitcointalk.org/index.php?topic=91806.msg1012234#msg1012234 Earliest Block With A Spend]</ref>.
|-
! October 5
|| Exchange rates [http://newlibertystandard.wikifoundry.com/page/2009+Exchange+Rate published] by New Liberty Standard. $1 = 1,309.03 BTC (and [[User:theymos|theymos]] thought NLS was overcharging<ref>[http://bitcointalk.org/index.php?topic=104287.msg1143955#msg1143955 Historical Price Data for 2009]</ref>)
|-
! October 9
|| #bitcoin-dev channel registered on freenode IRC.
|-
! December 16
|| Bitcoin v0.2 released
|-
! December 30
|| First difficulty increase at 06:11:04 GMT
|}

=== 2010 ===
{| style="text-align: left"
|-
! width="8em" | February 6
|| [[Bitcoin Market]] established
|-
! May 22
|| laszlo first to buy pizza with Bitcoins agreeing upon paying 10,000 BTC for ~$25 worth of pizza courtesy of jercos<ref>[https://bitcointalk.org/index.php?topic=137.msg1195#msg1195 bitcointalk post] where laszlo confirmed having bought pizza</ref>
|-
! July 7
|| Bitcoin v0.3 released
|-
! July 11
|| Bitcoin v0.3 release mentioned on slashdot<ref>[http://news.slashdot.org/story/10/07/11/1747245/Bitcoin-Releases-Version-03 slashdot] metiones Bitcoin</ref>, bringing a large influx of new bitcoin users.
|-
! July 12
|| Beginning of a 10x increase in exchange value over a 5 day period, from about $0.008/BTC to $0.08/BTC
|-
! July 17
|| [[MtGox]] established
|-
! July 18
|| ArtForz generated his first block after establishing his personal OpenCL GPU hash farm
|-
! August 15
|| Bug in the bitcoin code allows a bad transaction into block 74638. Users quickly adopt fixed code and the "good" block chain overtook the bad one at a block height of 74691, 53 blocks later ([[Incidents#Value_overflow]]).
|-
! September 14
|| jgarzik [https://bitcointalk.org/index.php?topic=133.msg12921#msg12921 offered] 10,000 BTC (valued at ~$600-650) to puddinpop to open source their windows-based CUDA client
|-
! September 14
|| Block [http://blockexplorer.com/b/79764 79,764] is first to be mined using split allocation of the generation reward.
|-
! September 18
|| puddinpop [https://bitcointalk.org/index.php?topic=133.msg13135#msg13135 released] source to their windows-based CUDA client under MIT license
|-
! September 29
|| kermit [https://bitcointalk.org/index.php?topic=1306.0 discovered] a microtransactions exploit which precipitated the Bitcoin v0.3.13 release
|-
! October 01
|| [https://bitcointalk.org/?topic=1334.0 First public OpenCL miner] released
|-
! October 04
|| Original Bitcoin History wiki page (this page) established (ooh so meta) on Bitcoin.org's wiki.
|-
! October 07
|| Exchange rate started climbing up from $0.06/BTC after several flat months.
|-
! October 16
|| First recorded escrowed bitcoin trade conducted, between nanotube and Diablo-D3, escrowed by theymos.
|-
! October 17
|| [[Bitcoin_OTC|#bitcoin-otc]] trading channel established on freenode IRC.
|-
! October 28
|| First bitcoin short sale transaction initiated, with a loan of 100 BTC by nanotube to [[User:Kiba|kiba]], facilitated by the [[Bitcoin-otc|#bitcoin-otc]] market.
|-
! November 6
|| The [https://bitcointalk.org/index.php?topic=1672 Bitcoin economy passed US $1 million]. The MtGox price touched USD $0.50/BTC.
|-
! December 7
|| Bitcoind was compiled for the Nokia N900 mobile computer by doublec. The following day, ribuck sent him 0.42 BTC in the first portable-to-portable Bitcoin transaction.
|-
! December 9
|| The generation difficulty passed 10,000.
|-
|
|| First bitcoin call option contract sold, from nanotube to [[User:Sgornick|sgornick]], via the [[Bitcoin-otc|#bitcoin-otc]] market.
|-
! December 16
|| [http://mining.bitcoin.cz/ Bitcoin Pooled Mining], operated by slush, found its first block
|}

=== 2011 ===
{| style="text-align: left"
|-
! width="8em" | January 2
|| [[Tonal Bitcoin]] units standardized.
|-
! January 8
|| [[History of Bitcoin]] page (this page) created after replicating from original Bitcoin History page on Bitcoin.org.
|-
|
|| Bitcoin Pooled Mining reached a total of 10,000 Mhash/s
|-
! January 27
|| Largest numeric value ever traded for bitcoins thus far occurred on this date. Three currency bills from Zimbabwe, known as Zimdollars, were traded on [[Bitcoin-otc|#bitcoin-otc]] at the rate of 4 BTC for each of the one-hundred trillion dollar ($100,000,000,000,000) Zimbabwe notes<ref>Serial numbers for Zimdollars sold: AA1669317, AA1669318 and AA1669319</ref>
|-
! January 28
|| Block 105000 was generated. This means that 5.25 million bitcoins have been generated, which is just over one-quarter of the eventual total of nearly 21 million.
|-
! February 9
|| Bitcoin reached parity with the US dollar, touching $1 per BTC at [[MtGox]].
|-
! February 10
|| Bitcoin.org website struggles to handle [https://bitcointalk.org/index.php?topic=3444.0 traffic] resulting from mentions on Slashdot<ref>[http://news.slashdot.org/story/11/02/10/189246/Online-Only-Currency-BitCoin-Reaches-Dollar-Parity Online-Only Currency BitCoin Reaches Dollar Parity]</ref>, Hacker News and Twitter following the news that parity had been reached.
|-
! February 14
|| A vehicle was, for the first time, offered in exchange for a certain number of bitcoins<ref>[https://bitcointalk.org/index.php?topic=3485.0 Car for Sale - Australia]</ref>.
|-
! March 1
|| [[MagicalTux]] buys mtgox.com from its founder [[Jed McCaleb]]
|-
! March 6
|| Total Bitcoin network computation speed for a short time reached a new high of almost 900Ghash/sec, dropping to 500Ghash/sec soon after. Some speculate that this was due to some supercomputer or bot-net that joined the network ([http://bitcoin.atspace.com/mysteryminer.html mystery miner]).
|-
! March 18
|| BTC/USD exchange rate reaches a 6-week low point at almost $0.70/BTC, after what appeared to be a short burst of, possibly automated, BTC sales at progressively lower prices. BTC price had been declining since the February 9 high.
|-
! March 22
|| [https://www.weusecoins.com/ WeUseCoins] releases the viral video What Is Bitcoin? which has had more than 6.4 million views.
|-
! March 25
|| Difficulty decreased nearly 10%. A decrease has only occurred once before, and this decrease of nearly 10% was the largest.
|-
! March 27
|| The first market for exchanging bitcoins to and from the British Pound Sterling BTC/GBP, [[Britcoin]], opens.
|-
! March 31
|| The first market for exchanging bitcoins to and from Brazilian Reals, [[Bitcoin Brazil]], opens.
|-
! April 5
|| The first market for exchanging bitcoins to and from the Polish złoty, [[BitMarket.eu]], opens.
|-
! April 12
|| First bitcoin put option contract sold via the [[Bitcoin-otc|#bitcoin-otc]] market.
|-
! April 16
|| TIME does [http://techland.time.com/2011/04/16/online-cash-bitcoin-could-challenge-governments/ an article on Bitcoin].
|-
! April 23
|| BTC/USD exchange rate reaches and passes parity with the Euro (EUR) on [[MtGox]] exchange.
|-
|
|| BTC/USD exchange rate reaches and passes parity with the British Sterling Pound (GBP) on [[MtGox]] exchange.
|-
|
|| Value of the Bitcoin money stock at current exchange rate passes $10 million USD threshold.
|-
! April 27
|| [[VirWoX]] opens first market to trade bitcoins against a virtual currency on BTC/SL (Second Life Lindens) exchange.
|-
! April 30
|| The generation difficulty passed 100,000.
|-
! June 2
|| The exchange rate at [[MtGox]] touched 10 USD per BTC.
|-
! June 3
|| [[Tonal Bitcoin]] reached parity with the US cent, touching 1¢ per TBC at [[Bitcoin Market]].
|-
! June 8
|| The [[MtGox]] exchange rate peaked at 31.91 USD, at a "market capitalization" of about $206 M [http://bitcoin.stackexchange.com/questions/2047/market-capitalization-over-time].
|-
! June 12
|| The [[MtGox]] exchange rate briefly dropped to near 10 USD four days after the peak, in its largest percentage price retreat to date.
|-
! June 13
|| Forum user allinvain claimed to have had [http://forum.bitcoin.org/index.php?topic=16457.0 25,000 BTC stolen] from his Bitcoin wallet (approx. USD equivalent $375,000).
|-
! June 19
|| The MtGox database was compromised and the user table was leaked, containing details of 60,000 usernames, email addresses and password hashes, some of which were overly simple to brute force passwords.
|-
! June 19
|| Someone was able to access an admin account at MtGox and issue sell orders for hundreds of thousands of fake bitcoins, forcing the MtGox price down from $17.51 per bitcoin to $0.01. MtGox announced that these trades would be reversed. Trading was halted at MtGox for 7 days (and also briefly at TradeHill and Britcoin while their security was reviewed).
|-
! June 19
|| Some of the users on the leaked MtGox database had used the same username at MyBitcoin and had their passwords hacked. About 600 of them had their balance [http://forum.bitcoin.org/index.php?topic=22221.msg279396#msg279396 stolen from their MyBitcoin accounts]. One user lost over 2000 BTC.
|-
! June 20
|| The EFF announced that it was no longer accepting Bitcoin donations due to legal uncertainties.
|-
! June 24
|| The generation difficulty passed 1,000,000 with Block [http://blockexplorer.com/b/133056 133056].
|-
! July 19
|| "Let it go on record that at 4:05pm CET [19 July 2011], my manager Tadek was the first person in the world to receive [testnet] Bitcoins via NFC ;)" - Mike Hearn
|-
! July 22
|| [[BitCoins Mobile]], the first Bitcoin application for iPad was released by [http://www.intervex.net Intervex Digital].
|-
! July 26
|| [http://www.room77.de/ Room77] [https://bitcointalk.org/index.php?topic=32162.0 becomes] the first brick-and-mortar business (bar) to accept Bitcoin as a means of payment.
|-
! July 30
|| [http://pastebin.com/raw.php?i=BUB3dygQ Tribute to Len Sassaman] included in the blockchain<ref>[http://bitcointalk.org/index.php?topic=33618.msg420597#msg420597 A Tribute to Len "rabbi" Sassama]</ref>.
|-
! August 20
|| First Bitcoin Conference and World Expo held, in NYC.<ref>[http://bitcoinme.com/index.php/conference/ New York Conference 2011]</ref>
|-
! August 23
|| [[P2Pool]], the first P2P decentralized pool, mines its first Bitcoin mainnet block (Block [http://blockexplorer.com/b/142312 142,312]).
|-
! August 30
|| Difficulty adjustment at block [http://blockexplorer.com/b/143136 143,136] marks the first back-to-back drop.
|-
! November 15
|| First CVE (CVE-2011-4447) assigned to a Bitcoin client exploit.
|-
! November 25
|| First European Bitcoin Conference in Prague, Czech Rep.<ref>[http://bitgroups.org/ Prague Conference 2011]</ref>
|-
! December 12
|| Largest amount of fees, to-date, in a single transaction, and most fees in a single block. A [http://blockexplorer.com/tx/1d7749c65c90c32f5e2c036217a2574f3f4403da39174626b246eefa620b58d9 transaction] paid 171 BTC in fees in [http://blockexplorer.com/b/157235 block 157235]<ref>[http://bitcointalk.org/index.php?topic=88423.msg973509#msg973509 Largest fee ever?]</ref>.
|}

=== 2012 ===
{| style="text-align: left"
|-
! width="8em" | March 1
|| Largest theft of bitcoins to-date occurred (near 50K BTC) after security breach at web host Linode.
|-
! width="8em" | April 1
|| Pay-to-script-hash ([[P2SH]]) as defined through [[BIP 0016]] goes live.
|-
! May 08
|| A single service, [[Satoshi Dice]] becomes responsible for over half the transaction volume on the Bitcoin blockchain.
|-
! June 3
|| Largest block (most transactions), to-date (June 3), is [http://BlockExplorer.com/b/181919 block 181919] with 1322 transactions<ref>[http://bitcointalk.org/index.php?topic=85353.msg939859#msg939859 Largest block to date]</ref>.
|-
! July 22
|| One millionth topic reply was posted on the unofficial [[Bitcoin Forum]] <ref>[https://bitcointalk.org/index.php?topic=94608.0 Topic about one millionth forum post]</ref>.
|-
! September 15-16
|| Bitcoin Conference in London <ref>[http://bitcoin2012.com/ London Conference 2012]</ref>.
|-
! September 27
|| Formation of the [[Bitcoin Foundation]].
|-
! November 28
|| Halving day. [http://blockexplorer.com/b/210000 Block 210,000] is the first with a block reward subsidy of only 25 BTC.
|-
! December 6
|| First Bitcoin exchange [https://bitcointalk.org/index.php?topic=129461.0 licensed "as a bank" in europe] (actually a PSP which is like a bank, without debt-money issuing).
|}

=== 2013 ===
{| style="text-align: left"
|-
! width="8em" | February 19
|| Bitcoin Client v0.8 released featuring improved download speed and [https://en.wikipedia.org/wiki/Bloom_filter Bloom Filtering]
|-
! February 28
|| The [[MtGox]] exchange rate broke the June 8 2011 peak of 31.91 USD. The first all time high since 601 days
|-
! March 12
|| A previously undiscovered protocol rule results in a [http://bitcoin.org/chainfork.html hard fork of the 0.8.0 reference client].
|-
! March 18
|| The United States federal agency charged with enforcing laws against money laundering (FinCEN) declares that Bitcoin users are subject to regulation only at the point of USD-BTC exchange.<ref>[http://arstechnica.com/tech-policy/2013/03/us-regulator-bitcoin-exchanges-must-comply-with-money-laundering-laws/ US regulator: Bitcoin exchanges must comply with money-laundering laws]</ref>
|-
! March 28
|| Total Bitcoin market cap passes $1 billion. <ref>http://spectrum.ieee.org/computing/networks/bitcoin-hits-1billion</ref>
|-
! April 1
|| Bitcoin price breaks 100 USD on [[MtGox]] and other major exchanges.
|-
|}

==See Also==

* [[Bitcoin Firsts]]
* [[Press]]
* [https://bitcoinhelp.net/know/more/price-chart-history Bitcoin Price Chart with Historic Events]

==References==
<references />

Block size limit controversy

2015-06-17T15:37:02Z

Sunnankar: /* Arguments in opposition to increasing the blocksize */

== Introduction ==

Blocks are limited to 1MB in size. Miners can mine blocks upto the 1MB fixed limit. Any block larger than 1MB is invalid.

The blocksize limit has the dual purpose of discouraging economically frivolous transactions from flooding the blockchain and encouraging transactions fees to incentivize miners.

The fixed blocksize limit cannot be modified without a hard fork.

Hard forks require adoption by virtually all of the bitcoin participants.

== Arguments in favor of increasing the blocksize ==
* Larger blocks will provide greater utility for users of the network
* More transactions per second
* Increased space for extensibility like SNARKs, Mastercoin, Counterparty, etc.
* Faster confirmation times with lower fees required

== Arguments in opposition to increasing the blocksize ==
* A hard fork requires waiting for sufficient consensus.
* However an emergency hard fork can achieve consensus for deployment on a short time period if needed.
* Risk of catastrophic consensus failure<ref>https://www.mail-archive.com/bitcoin-development@lists.sourceforge.net/msg08276.html</ref>
* Orphan rate amplification, more reorgs and double-spends due to slower propagation speeds.
* European/American pools at more of a disadvantage compared to the Chinese pools{{why}}
* No amount of max block size would support all the world's future transactions on the main blockchain (various types of off-chain transactions are the only long-term solution)
* Fast block propagation is either not clearly viable, or (eg, IBLT) creates centralised controls.

=== Damage to decentalization ===
* Bitcoin is only useful if it is decentralized because centralization requires trust. Bitcoins value proposition is trustlessness.
* The larger the hash-rate a single miner controls, the more centralized Bitcoin becomes and the more trust using Bitcoin requires.
* Running your own full node while mining rather than giving another entity the right to your hash-power decreases the hash-rate of large miners. Those who control hash-power are able to control their own hash power if and only if they run a full node.
* Less individuals who control hash-power will run full nodes if running one becomes more expensive<ref>https://www.weusecoins.com/why-blocksize-limit-keeps-bitcoin-free-decentralized/</ref>.
* Larger blocks leads to more expensive full nodes.
* Therefore, larger blocks lead to less hashers running full nodes, which leads to centralized entities having more power, which makes Bitcoin require more trust, which weakens Bitcoins value proposition.

== Entities positions ==
Positions below are based on a suggested fixed block size increase to 20MiB. Positions against these larger blocks do not necessarily imply that they are against an increase in general, and may instead support a smaller and/or gradual increase.
{| class="wikitable sortable"
! Entity
! Supports Larger Blocks
! Supports Hard Fork
|-
| Bitcoinpaygate
| {{No|No: "We do NOT support the blocksize increase"}}<ref>http://www.reddit.com/r/Bitcoin/comments/37y8wm/list_of_bitcoin_services_that_supportoppose/crqsnqp</ref>
|
|-
| Bitrated
| {{No}} "At this time, I oppose increasing the block size limit as per Gavin's proposal" - Nadav Ivgi (founder)<ref>https://twitter.com/shesek/status/605005384026177537</ref>
|
|-
| [[F2Pool]]
| {{No|No: "We do support bigger blocks and sooner rather than later. But we cannot handle 20 MB blocks right now. ... I think we can accept 5MB block at most."}}<ref>http://sourceforge.net/p/bitcoin/mailman/message/34157036/],[http://sourceforge.net/p/bitcoin/mailman/message/34158911/</ref>
|
|-
| [[GreenAddress]]
| {{No|No: "In our mind increasing the block size like this is just pushing the problem a little further at potentially unfixable costs."}}<ref>http://www.reddit.com/r/Bitcoin/comments/35anax/list_of_bitcoin_services_that_support_increasing/cr2mq84</ref>
|
|-
| [[MPEx]]
| {{No}}<ref>http://log.bitcoin-assets.com//?date=07-01-2015#967332</ref>
|
|-
| [[Paymium]]
| {{No|No: "<nowiki>[allow]</nowiki> a sane transaction fee market to emerge, by letting the blocks actually fill-up."}} - CTO David Francois<ref>http://fr.anco.is/2015/gavineries/</ref>
|
|-
| Ethereum 
| {{Neutral|Neutral: "If <nowiki>[the niche of digital gold]</nowiki> is what Bitcoin users want, then they should keep the limit, and perhaps even decrease it. But if Bitcoin users want to be a payment system, then up it must go."}} - Vitalik Buterin (founder)<ref>http://www.reddit.com/r/ethereum/comments/380q61/i_know_this_may_not_directly_be_ethereum_related/crrofl6</ref>
|
|-
| [[Armory]]
| {{Yes}} "This *is* urgent and needs to be handled right now, and I believe Gavin
has the best approach to this." - CEO Alan Reiner<ref>http://sourceforge.net/p/bitcoin/mailman/message/34093337/</ref>
|
|-
| BitcoinReminder
| {{Yes|Yes: "BitcoinReminder.com also supports 20MB blocks (or even more?"}}<ref>http://www.reddit.com/r/Bitcoin/comments/37y8wm/list_of_bitcoin_services_that_supportoppose/crs9ytd</ref>
|
|-
| BitHours
| {{Yes|Yes: "We support @gavinandresen and his proposal for 20mb blocks"}}<ref>https://twitter.com/bithours/status/605131647747358721</ref>
|
|-
| [[BitPay]]
| {{Yes}} "Agreed (but optimistic this will be the last and only time block size needs to increase)" - CEO Stephen Pair<ref>https://twitter.com/spair/status/595341090317799424</ref>
|
|-
| Bittiraha.fi
| {{Yes|Yes: "We are supporting increasing #Bitcoin max block size to 20MB."}}<ref>https://twitter.com/Bittirahafi/status/596682373028311040</ref> "I'm strongly in favor of the block size cap increase to 20MB." - CEO Henry Brade<ref>https://twitter.com/Technom4ge/status/596334370803326978</ref>
| {{Yes}} "And I'm in favor of releasing a version with this change even with opposition." - CEO Henry Brade<ref>https://twitter.com/Technom4ge/status/596334370803326978</ref>
|-
| [[Blockchain.info]]
|{{Yes}} "It is time to increase the block size. Agree with @gavinandresen" - CEO Peter Smith<ref>https://twitter.com/OneMorePeter/status/595676380320407553</ref> "Scaling #bitcoin is a big deal. Increase the block size." - Nic Cary<ref>https://twitter.com/niccary/status/595707211994763264</ref>
|
|-
| Breadwallet
| {{Yes}} "[...] in support of the Gavin's 20Mb block proposal." - CEO Aaron Voisine<ref>http://sourceforge.net/p/bitcoin/mailman/message/34096857/</ref>
|
|-
| [[BTC Guild]]
| {{Yes}} "Needs to happen, but needs future expansion built in at a reasonable rate." - Eleuthria<ref>https://www.reddit.com/r/Bitcoin/comments/370rko/21_inc_engineer_everyone_assumes_humans_will_be/crjfnpg?context=3</ref>
|
|-
| BX.in.th
| {{Yes|Yes: "<nowiki>http://BX.in.th</nowiki> will support the 20MB block size"}}<ref>https://twitter.com/BitcoinThai/status/605022509101023232</ref>
|
|-
| [[Coinbase (business)|CoinBase]]
| {{Yes|Yes: "Coinbase supports increasing the maximum block size"}}<ref>https://twitter.com/coinbase/status/595741967759335426</ref> "Why we should increase the block size" - CEO Brian Armstrong<ref>https://twitter.com/brian_armstrong/status/595453245884997634</ref>
|
|-
| [[Dr. Adam Back (individual)|Dr. Adam Back]]
| {{Yes|Yes: "For the record I am not aware of a single person who has said they do not agree with scaling Bitcoin. Changing a constant is not the hard-part. The hard part is validating a plan and the other factors that go into it. It's not a free choice it is a security/scalability tradeoff. No one will thank us if we "scale" bitcoin but break it in hard to recover ways at the same time."}} <ref>https://www.mail-archive.com/bitcoin-development@lists.sourceforge.net/msg08276.html</ref>
| {{No}} "I strongly urge that we return to the existing collaborative constructive review process that has been used for the last 4 years which is a consensus by design to prevent one rogue person from inserting a backdoor, or lobbying for a favoured change on behalf of a special interest group, or working for bad actor" - Dr. Adam Back<ref>https://www.mail-archive.com/bitcoin-development@lists.sourceforge.net/msg08276.html</ref>
|
|-
| Kryptoradio
| {{Yes}} "#Kryptoradio dev @zouppen supports 20MB block size in #bitcoin." - Joel Lehtonen<ref>https://twitter.com/koodilehto/status/596675967667568641</ref>
|
|-
| OKCoin
| {{Yes|Yes: "OKCoin's tech team believes it's the right decision"}}<ref>https://twitter.com/okcoinbtc/status/598412795240009728</ref>
|
|-
| Third Key Solutions
| {{Yes}} "Gavin is right. The time to increase the block size limit is before transaction processing shows congestion problems." - CTO Andreas Antonopoulos<ref>https://twitter.com/aantonop/status/595601619581964289</ref>
|
|-
| Xapo
| {{Yes|Yes: "One meg is not enough: Xapo supports increasing the maximum block size"}} - CEO Wences Casares<ref>https://twitter.com/wences/status/595768917907402752</ref>
|
|}

Block size limit controversy

2015-06-17T15:36:20Z

Sunnankar: /* Arguments in favor of increasing the blocksize */

== Introduction ==

Blocks are limited to 1MB in size. Miners can mine blocks upto the 1MB fixed limit. Any block larger than 1MB is invalid.

The blocksize limit has the dual purpose of discouraging economically frivolous transactions from flooding the blockchain and encouraging transactions fees to incentivize miners.

The fixed blocksize limit cannot be modified without a hard fork.

Hard forks require adoption by virtually all of the bitcoin participants.

== Arguments in favor of increasing the blocksize ==
* Larger blocks will provide greater utility for users of the network
* More transactions per second
* Increased space for extensibility like SNARKs, Mastercoin, Counterparty, etc.
* Faster confirmation times with lower fees required

== Arguments in opposition to increasing the blocksize ==
* A hard fork requires waiting for sufficient consensus.
* However an emergency hard fork can achieve consensus for deployment on a short time period if needed.
* Risk of catastrophic consensus failure{{clarification needed}}
* Orphan rate amplification, more reorgs and double-spends due to slower propagation speeds.
* European/American pools at more of a disadvantage compared to the Chinese pools{{why}}
* No amount of max block size would support all the world's future transactions on the main blockchain (various types of off-chain transactions are the only long-term solution)
* Fast block propagation is either not clearly viable, or (eg, IBLT) creates centralised controls.

=== Damage to decentalization ===
* Bitcoin is only useful if it is decentralized because centralization requires trust. Bitcoins value proposition is trustlessness.
* The larger the hash-rate a single miner controls, the more centralized Bitcoin becomes and the more trust using Bitcoin requires.
* Running your own full node while mining rather than giving another entity the right to your hash-power decreases the hash-rate of large miners. Those who control hash-power are able to control their own hash power if and only if they run a full node.
* Less individuals who control hash-power will run full nodes if running one becomes more expensive<ref>https://www.weusecoins.com/why-blocksize-limit-keeps-bitcoin-free-decentralized/</ref>.
* Larger blocks leads to more expensive full nodes.
* Therefore, larger blocks lead to less hashers running full nodes, which leads to centralized entities having more power, which makes Bitcoin require more trust, which weakens Bitcoins value proposition.

== Entities positions ==
Positions below are based on a suggested fixed block size increase to 20MiB. Positions against these larger blocks do not necessarily imply that they are against an increase in general, and may instead support a smaller and/or gradual increase.
{| class="wikitable sortable"
! Entity
! Supports Larger Blocks
! Supports Hard Fork
|-
| Bitcoinpaygate
| {{No|No: "We do NOT support the blocksize increase"}}<ref>http://www.reddit.com/r/Bitcoin/comments/37y8wm/list_of_bitcoin_services_that_supportoppose/crqsnqp</ref>
|
|-
| Bitrated
| {{No}} "At this time, I oppose increasing the block size limit as per Gavin's proposal" - Nadav Ivgi (founder)<ref>https://twitter.com/shesek/status/605005384026177537</ref>
|
|-
| [[F2Pool]]
| {{No|No: "We do support bigger blocks and sooner rather than later. But we cannot handle 20 MB blocks right now. ... I think we can accept 5MB block at most."}}<ref>http://sourceforge.net/p/bitcoin/mailman/message/34157036/],[http://sourceforge.net/p/bitcoin/mailman/message/34158911/</ref>
|
|-
| [[GreenAddress]]
| {{No|No: "In our mind increasing the block size like this is just pushing the problem a little further at potentially unfixable costs."}}<ref>http://www.reddit.com/r/Bitcoin/comments/35anax/list_of_bitcoin_services_that_support_increasing/cr2mq84</ref>
|
|-
| [[MPEx]]
| {{No}}<ref>http://log.bitcoin-assets.com//?date=07-01-2015#967332</ref>
|
|-
| [[Paymium]]
| {{No|No: "<nowiki>[allow]</nowiki> a sane transaction fee market to emerge, by letting the blocks actually fill-up."}} - CTO David Francois<ref>http://fr.anco.is/2015/gavineries/</ref>
|
|-
| Ethereum 
| {{Neutral|Neutral: "If <nowiki>[the niche of digital gold]</nowiki> is what Bitcoin users want, then they should keep the limit, and perhaps even decrease it. But if Bitcoin users want to be a payment system, then up it must go."}} - Vitalik Buterin (founder)<ref>http://www.reddit.com/r/ethereum/comments/380q61/i_know_this_may_not_directly_be_ethereum_related/crrofl6</ref>
|
|-
| [[Armory]]
| {{Yes}} "This *is* urgent and needs to be handled right now, and I believe Gavin
has the best approach to this." - CEO Alan Reiner<ref>http://sourceforge.net/p/bitcoin/mailman/message/34093337/</ref>
|
|-
| BitcoinReminder
| {{Yes|Yes: "BitcoinReminder.com also supports 20MB blocks (or even more?"}}<ref>http://www.reddit.com/r/Bitcoin/comments/37y8wm/list_of_bitcoin_services_that_supportoppose/crs9ytd</ref>
|
|-
| BitHours
| {{Yes|Yes: "We support @gavinandresen and his proposal for 20mb blocks"}}<ref>https://twitter.com/bithours/status/605131647747358721</ref>
|
|-
| [[BitPay]]
| {{Yes}} "Agreed (but optimistic this will be the last and only time block size needs to increase)" - CEO Stephen Pair<ref>https://twitter.com/spair/status/595341090317799424</ref>
|
|-
| Bittiraha.fi
| {{Yes|Yes: "We are supporting increasing #Bitcoin max block size to 20MB."}}<ref>https://twitter.com/Bittirahafi/status/596682373028311040</ref> "I'm strongly in favor of the block size cap increase to 20MB." - CEO Henry Brade<ref>https://twitter.com/Technom4ge/status/596334370803326978</ref>
| {{Yes}} "And I'm in favor of releasing a version with this change even with opposition." - CEO Henry Brade<ref>https://twitter.com/Technom4ge/status/596334370803326978</ref>
|-
| [[Blockchain.info]]
|{{Yes}} "It is time to increase the block size. Agree with @gavinandresen" - CEO Peter Smith<ref>https://twitter.com/OneMorePeter/status/595676380320407553</ref> "Scaling #bitcoin is a big deal. Increase the block size." - Nic Cary<ref>https://twitter.com/niccary/status/595707211994763264</ref>
|
|-
| Breadwallet
| {{Yes}} "[...] in support of the Gavin's 20Mb block proposal." - CEO Aaron Voisine<ref>http://sourceforge.net/p/bitcoin/mailman/message/34096857/</ref>
|
|-
| [[BTC Guild]]
| {{Yes}} "Needs to happen, but needs future expansion built in at a reasonable rate." - Eleuthria<ref>https://www.reddit.com/r/Bitcoin/comments/370rko/21_inc_engineer_everyone_assumes_humans_will_be/crjfnpg?context=3</ref>
|
|-
| BX.in.th
| {{Yes|Yes: "<nowiki>http://BX.in.th</nowiki> will support the 20MB block size"}}<ref>https://twitter.com/BitcoinThai/status/605022509101023232</ref>
|
|-
| [[Coinbase (business)|CoinBase]]
| {{Yes|Yes: "Coinbase supports increasing the maximum block size"}}<ref>https://twitter.com/coinbase/status/595741967759335426</ref> "Why we should increase the block size" - CEO Brian Armstrong<ref>https://twitter.com/brian_armstrong/status/595453245884997634</ref>
|
|-
| [[Dr. Adam Back (individual)|Dr. Adam Back]]
| {{Yes|Yes: "For the record I am not aware of a single person who has said they do not agree with scaling Bitcoin. Changing a constant is not the hard-part. The hard part is validating a plan and the other factors that go into it. It's not a free choice it is a security/scalability tradeoff. No one will thank us if we "scale" bitcoin but break it in hard to recover ways at the same time."}} <ref>https://www.mail-archive.com/bitcoin-development@lists.sourceforge.net/msg08276.html</ref>
| {{No}} "I strongly urge that we return to the existing collaborative constructive review process that has been used for the last 4 years which is a consensus by design to prevent one rogue person from inserting a backdoor, or lobbying for a favoured change on behalf of a special interest group, or working for bad actor" - Dr. Adam Back<ref>https://www.mail-archive.com/bitcoin-development@lists.sourceforge.net/msg08276.html</ref>
|
|-
| Kryptoradio
| {{Yes}} "#Kryptoradio dev @zouppen supports 20MB block size in #bitcoin." - Joel Lehtonen<ref>https://twitter.com/koodilehto/status/596675967667568641</ref>
|
|-
| OKCoin
| {{Yes|Yes: "OKCoin's tech team believes it's the right decision"}}<ref>https://twitter.com/okcoinbtc/status/598412795240009728</ref>
|
|-
| Third Key Solutions
| {{Yes}} "Gavin is right. The time to increase the block size limit is before transaction processing shows congestion problems." - CTO Andreas Antonopoulos<ref>https://twitter.com/aantonop/status/595601619581964289</ref>
|
|-
| Xapo
| {{Yes|Yes: "One meg is not enough: Xapo supports increasing the maximum block size"}} - CEO Wences Casares<ref>https://twitter.com/wences/status/595768917907402752</ref>
|
|}

Block size limit controversy

2015-06-17T15:30:45Z

Sunnankar: /* Entities positions */

== Introduction ==

Blocks are limited to 1MB in size. Miners can mine blocks upto the 1MB fixed limit. Any block larger than 1MB is invalid.

The blocksize limit has the dual purpose of discouraging economically frivolous transactions from flooding the blockchain and encouraging transactions fees to incentivize miners.

The fixed blocksize limit cannot be modified without a hard fork.

Hard forks require adoption by virtually all of the bitcoin participants.

== Arguments in favor of increasing the blocksize ==
* Bigger blocks (more transactions per second)

== Arguments in opposition to increasing the blocksize ==
* A hard fork requires waiting for sufficient consensus.
* However an emergency hard fork can achieve consensus for deployment on a short time period if needed.
* Risk of catastrophic consensus failure{{clarification needed}}
* Orphan rate amplification, more reorgs and double-spends due to slower propagation speeds.
* European/American pools at more of a disadvantage compared to the Chinese pools{{why}}
* No amount of max block size would support all the world's future transactions on the main blockchain (various types of off-chain transactions are the only long-term solution)
* Fast block propagation is either not clearly viable, or (eg, IBLT) creates centralised controls.

=== Damage to decentalization ===
* Bitcoin is only useful if it is decentralized because centralization requires trust. Bitcoins value proposition is trustlessness.
* The larger the hash-rate a single miner controls, the more centralized Bitcoin becomes and the more trust using Bitcoin requires.
* Running your own full node while mining rather than giving another entity the right to your hash-power decreases the hash-rate of large miners. Those who control hash-power are able to control their own hash power if and only if they run a full node.
* Less individuals who control hash-power will run full nodes if running one becomes more expensive<ref>https://www.weusecoins.com/why-blocksize-limit-keeps-bitcoin-free-decentralized/</ref>.
* Larger blocks leads to more expensive full nodes.
* Therefore, larger blocks lead to less hashers running full nodes, which leads to centralized entities having more power, which makes Bitcoin require more trust, which weakens Bitcoins value proposition.

== Entities positions ==
Positions below are based on a suggested fixed block size increase to 20MiB. Positions against these larger blocks do not necessarily imply that they are against an increase in general, and may instead support a smaller and/or gradual increase.
{| class="wikitable sortable"
! Entity
! Supports Larger Blocks
! Supports Hard Fork
|-
| Bitcoinpaygate
| {{No|No: "We do NOT support the blocksize increase"}}<ref>http://www.reddit.com/r/Bitcoin/comments/37y8wm/list_of_bitcoin_services_that_supportoppose/crqsnqp</ref>
|
|-
| Bitrated
| {{No}} "At this time, I oppose increasing the block size limit as per Gavin's proposal" - Nadav Ivgi (founder)<ref>https://twitter.com/shesek/status/605005384026177537</ref>
|
|-
| [[F2Pool]]
| {{No|No: "We do support bigger blocks and sooner rather than later. But we cannot handle 20 MB blocks right now. ... I think we can accept 5MB block at most."}}<ref>http://sourceforge.net/p/bitcoin/mailman/message/34157036/],[http://sourceforge.net/p/bitcoin/mailman/message/34158911/</ref>
|
|-
| [[GreenAddress]]
| {{No|No: "In our mind increasing the block size like this is just pushing the problem a little further at potentially unfixable costs."}}<ref>http://www.reddit.com/r/Bitcoin/comments/35anax/list_of_bitcoin_services_that_support_increasing/cr2mq84</ref>
|
|-
| [[MPEx]]
| {{No}}<ref>http://log.bitcoin-assets.com//?date=07-01-2015#967332</ref>
|
|-
| [[Paymium]]
| {{No|No: "<nowiki>[allow]</nowiki> a sane transaction fee market to emerge, by letting the blocks actually fill-up."}} - CTO David Francois<ref>http://fr.anco.is/2015/gavineries/</ref>
|
|-
| Ethereum 
| {{Neutral|Neutral: "If <nowiki>[the niche of digital gold]</nowiki> is what Bitcoin users want, then they should keep the limit, and perhaps even decrease it. But if Bitcoin users want to be a payment system, then up it must go."}} - Vitalik Buterin (founder)<ref>http://www.reddit.com/r/ethereum/comments/380q61/i_know_this_may_not_directly_be_ethereum_related/crrofl6</ref>
|
|-
| [[Armory]]
| {{Yes}} "This *is* urgent and needs to be handled right now, and I believe Gavin
has the best approach to this." - CEO Alan Reiner<ref>http://sourceforge.net/p/bitcoin/mailman/message/34093337/</ref>
|
|-
| BitcoinReminder
| {{Yes|Yes: "BitcoinReminder.com also supports 20MB blocks (or even more?"}}<ref>http://www.reddit.com/r/Bitcoin/comments/37y8wm/list_of_bitcoin_services_that_supportoppose/crs9ytd</ref>
|
|-
| BitHours
| {{Yes|Yes: "We support @gavinandresen and his proposal for 20mb blocks"}}<ref>https://twitter.com/bithours/status/605131647747358721</ref>
|
|-
| [[BitPay]]
| {{Yes}} "Agreed (but optimistic this will be the last and only time block size needs to increase)" - CEO Stephen Pair<ref>https://twitter.com/spair/status/595341090317799424</ref>
|
|-
| Bittiraha.fi
| {{Yes|Yes: "We are supporting increasing #Bitcoin max block size to 20MB."}}<ref>https://twitter.com/Bittirahafi/status/596682373028311040</ref> "I'm strongly in favor of the block size cap increase to 20MB." - CEO Henry Brade<ref>https://twitter.com/Technom4ge/status/596334370803326978</ref>
| {{Yes}} "And I'm in favor of releasing a version with this change even with opposition." - CEO Henry Brade<ref>https://twitter.com/Technom4ge/status/596334370803326978</ref>
|-
| [[Blockchain.info]]
|{{Yes}} "It is time to increase the block size. Agree with @gavinandresen" - CEO Peter Smith<ref>https://twitter.com/OneMorePeter/status/595676380320407553</ref> "Scaling #bitcoin is a big deal. Increase the block size." - Nic Cary<ref>https://twitter.com/niccary/status/595707211994763264</ref>
|
|-
| Breadwallet
| {{Yes}} "[...] in support of the Gavin's 20Mb block proposal." - CEO Aaron Voisine<ref>http://sourceforge.net/p/bitcoin/mailman/message/34096857/</ref>
|
|-
| [[BTC Guild]]
| {{Yes}} "Needs to happen, but needs future expansion built in at a reasonable rate." - Eleuthria<ref>https://www.reddit.com/r/Bitcoin/comments/370rko/21_inc_engineer_everyone_assumes_humans_will_be/crjfnpg?context=3</ref>
|
|-
| BX.in.th
| {{Yes|Yes: "<nowiki>http://BX.in.th</nowiki> will support the 20MB block size"}}<ref>https://twitter.com/BitcoinThai/status/605022509101023232</ref>
|
|-
| [[Coinbase (business)|CoinBase]]
| {{Yes|Yes: "Coinbase supports increasing the maximum block size"}}<ref>https://twitter.com/coinbase/status/595741967759335426</ref> "Why we should increase the block size" - CEO Brian Armstrong<ref>https://twitter.com/brian_armstrong/status/595453245884997634</ref>
|
|-
| [[Dr. Adam Back (individual)|Dr. Adam Back]]
| {{Yes|Yes: "For the record I am not aware of a single person who has said they do not agree with scaling Bitcoin. Changing a constant is not the hard-part. The hard part is validating a plan and the other factors that go into it. It's not a free choice it is a security/scalability tradeoff. No one will thank us if we "scale" bitcoin but break it in hard to recover ways at the same time."}} <ref>https://www.mail-archive.com/bitcoin-development@lists.sourceforge.net/msg08276.html</ref>
| {{No}} "I strongly urge that we return to the existing collaborative constructive review process that has been used for the last 4 years which is a consensus by design to prevent one rogue person from inserting a backdoor, or lobbying for a favoured change on behalf of a special interest group, or working for bad actor" - Dr. Adam Back<ref>https://www.mail-archive.com/bitcoin-development@lists.sourceforge.net/msg08276.html</ref>
|
|-
| Kryptoradio
| {{Yes}} "#Kryptoradio dev @zouppen supports 20MB block size in #bitcoin." - Joel Lehtonen<ref>https://twitter.com/koodilehto/status/596675967667568641</ref>
|
|-
| OKCoin
| {{Yes|Yes: "OKCoin's tech team believes it's the right decision"}}<ref>https://twitter.com/okcoinbtc/status/598412795240009728</ref>
|
|-
| Third Key Solutions
| {{Yes}} "Gavin is right. The time to increase the block size limit is before transaction processing shows congestion problems." - CTO Andreas Antonopoulos<ref>https://twitter.com/aantonop/status/595601619581964289</ref>
|
|-
| Xapo
| {{Yes|Yes: "One meg is not enough: Xapo supports increasing the maximum block size"}} - CEO Wences Casares<ref>https://twitter.com/wences/status/595768917907402752</ref>
|
|}

Block size limit controversy

2015-06-17T15:20:53Z

Sunnankar: /* Arguments in opposition to increasing the blocksize */

== Introduction ==

Blocks are limited to 1MB in size. Miners can mine blocks upto the 1MB fixed limit. Any block larger than 1MB is invalid.

The blocksize limit has the dual purpose of discouraging economically frivolous transactions from flooding the blockchain and encouraging transactions fees to incentivize miners.

The fixed blocksize limit cannot be modified without a hard fork.

Hard forks require adoption by virtually all of the bitcoin participants.

== Arguments in favor of increasing the blocksize ==
* Bigger blocks (more transactions per second)

== Arguments in opposition to increasing the blocksize ==
* A hard fork requires waiting for sufficient consensus.
* However an emergency hard fork can achieve consensus for deployment on a short time period if needed.
* Risk of catastrophic consensus failure{{clarification needed}}
* Orphan rate amplification, more reorgs and double-spends due to slower propagation speeds.
* European/American pools at more of a disadvantage compared to the Chinese pools{{why}}
* No amount of max block size would support all the world's future transactions on the main blockchain (various types of off-chain transactions are the only long-term solution)
* Fast block propagation is either not clearly viable, or (eg, IBLT) creates centralised controls.

=== Damage to decentalization ===
* Bitcoin is only useful if it is decentralized because centralization requires trust. Bitcoins value proposition is trustlessness.
* The larger the hash-rate a single miner controls, the more centralized Bitcoin becomes and the more trust using Bitcoin requires.
* Running your own full node while mining rather than giving another entity the right to your hash-power decreases the hash-rate of large miners. Those who control hash-power are able to control their own hash power if and only if they run a full node.
* Less individuals who control hash-power will run full nodes if running one becomes more expensive<ref>https://www.weusecoins.com/why-blocksize-limit-keeps-bitcoin-free-decentralized/</ref>.
* Larger blocks leads to more expensive full nodes.
* Therefore, larger blocks lead to less hashers running full nodes, which leads to centralized entities having more power, which makes Bitcoin require more trust, which weakens Bitcoins value proposition.

== Entities positions ==
Positions below are based on a suggested fixed block size increase to 20MiB. Positions against these larger blocks do not necessarily imply that they are against an increase in general, and may instead support a smaller and/or gradual increase.
{| class="wikitable sortable"
! Entity
! Supports Larger Blocks
! Supports Hard Fork
|-
| Bitcoinpaygate
| {{No|No: "We do NOT support the blocksize increase"}}<ref>http://www.reddit.com/r/Bitcoin/comments/37y8wm/list_of_bitcoin_services_that_supportoppose/crqsnqp</ref>
|
|-
| Bitrated
| {{No}} "At this time, I oppose increasing the block size limit as per Gavin's proposal" - Nadav Ivgi (founder)<ref>https://twitter.com/shesek/status/605005384026177537</ref>
|
|-
| [[F2Pool]]
| {{No|No: "We do support bigger blocks and sooner rather than later. But we cannot handle 20 MB blocks right now. ... I think we can accept 5MB block at most."}}<ref>http://sourceforge.net/p/bitcoin/mailman/message/34157036/],[http://sourceforge.net/p/bitcoin/mailman/message/34158911/</ref>
|
|-
| [[GreenAddress]]
| {{No|No: "In our mind increasing the block size like this is just pushing the problem a little further at potentially unfixable costs."}}<ref>http://www.reddit.com/r/Bitcoin/comments/35anax/list_of_bitcoin_services_that_support_increasing/cr2mq84</ref>
|
|-
| [[MPEx]]
| {{No}}<ref>http://log.bitcoin-assets.com//?date=07-01-2015#967332</ref>
|
|-
| [[Paymium]]
| {{No|No: "<nowiki>[allow]</nowiki> a sane transaction fee market to emerge, by letting the blocks actually fill-up."}} - CTO David Francois<ref>http://fr.anco.is/2015/gavineries/</ref>
|
|-
| Ethereum 
| {{Neutral|Neutral: "If <nowiki>[the niche of digital gold]</nowiki> is what Bitcoin users want, then they should keep the limit, and perhaps even decrease it. But if Bitcoin users want to be a payment system, then up it must go."}} - Vitalik Buterin (founder)<ref>http://www.reddit.com/r/ethereum/comments/380q61/i_know_this_may_not_directly_be_ethereum_related/crrofl6</ref>
|
|-
| [[Armory]]
| {{Yes}} "This *is* urgent and needs to be handled right now, and I believe Gavin
has the best approach to this." - CEO Alan Reiner<ref>http://sourceforge.net/p/bitcoin/mailman/message/34093337/</ref>
|
|-
| BitcoinReminder
| {{Yes|Yes: "BitcoinReminder.com also supports 20MB blocks (or even more?"}}<ref>http://www.reddit.com/r/Bitcoin/comments/37y8wm/list_of_bitcoin_services_that_supportoppose/crs9ytd</ref>
|
|-
| BitHours
| {{Yes|Yes: "We support @gavinandresen and his proposal for 20mb blocks"}}<ref>https://twitter.com/bithours/status/605131647747358721</ref>
|
|-
| [[BitPay]]
| {{Yes}} "Agreed (but optimistic this will be the last and only time block size needs to increase)" - CEO Stephen Pair<ref>https://twitter.com/spair/status/595341090317799424</ref>
|
|-
| Bittiraha.fi
| {{Yes|Yes: "We are supporting increasing #Bitcoin max block size to 20MB."}}<ref>https://twitter.com/Bittirahafi/status/596682373028311040</ref> "I'm strongly in favor of the block size cap increase to 20MB." - CEO Henry Brade<ref>https://twitter.com/Technom4ge/status/596334370803326978</ref>
| {{Yes}} "And I'm in favor of releasing a version with this change even with opposition." - CEO Henry Brade<ref>https://twitter.com/Technom4ge/status/596334370803326978</ref>
|-
| [[Blockchain.info]]
|{{Yes}} "It is time to increase the block size. Agree with @gavinandresen" - CEO Peter Smith<ref>https://twitter.com/OneMorePeter/status/595676380320407553</ref> "Scaling #bitcoin is a big deal. Increase the block size." - Nic Cary<ref>https://twitter.com/niccary/status/595707211994763264</ref>
|
|-
| Breadwallet
| {{Yes}} "[...] in support of the Gavin's 20Mb block proposal." - CEO Aaron Voisine<ref>http://sourceforge.net/p/bitcoin/mailman/message/34096857/</ref>
|
|-
| [[BTC Guild]]
| {{Yes}} "Needs to happen, but needs future expansion built in at a reasonable rate." - Eleuthria<ref>https://www.reddit.com/r/Bitcoin/comments/370rko/21_inc_engineer_everyone_assumes_humans_will_be/crjfnpg?context=3</ref>
|
|-
| BX.in.th
| {{Yes|Yes: "<nowiki>http://BX.in.th</nowiki> will support the 20MB block size"}}<ref>https://twitter.com/BitcoinThai/status/605022509101023232</ref>
|
|-
| [[Coinbase (business)|CoinBase]]
| {{Yes|Yes: "Coinbase supports increasing the maximum block size"}}<ref>https://twitter.com/coinbase/status/595741967759335426</ref> "Why we should increase the block size" - CEO Brian Armstrong<ref>https://twitter.com/brian_armstrong/status/595453245884997634</ref>
|
|-
| Kryptoradio
| {{Yes}} "#Kryptoradio dev @zouppen supports 20MB block size in #bitcoin." - Joel Lehtonen<ref>https://twitter.com/koodilehto/status/596675967667568641</ref>
|
|-
| OKCoin
| {{Yes|Yes: "OKCoin's tech team believes it's the right decision"}}<ref>https://twitter.com/okcoinbtc/status/598412795240009728</ref>
|
|-
| Third Key Solutions
| {{Yes}} "Gavin is right. The time to increase the block size limit is before transaction processing shows congestion problems." - CTO Andreas Antonopoulos<ref>https://twitter.com/aantonop/status/595601619581964289</ref>
|
|-
| Xapo
| {{Yes|Yes: "One meg is not enough: Xapo supports increasing the maximum block size"}} - CEO Wences Casares<ref>https://twitter.com/wences/status/595768917907402752</ref>
|
|}

AurumXChange Company

2015-06-17T15:18:02Z

Sunnankar: /* References */

Formerly bought, sold and exchanged Bitcoin [[MtGox]] [[redeemable code|redeemable codes]], [[Perfect Money]] [[Liberty Reserve]], [[Pecunix]], CosmicPay, C-Gold, VouchX, EURO SEPA transfers, USD wire transfers, and GBP transfers.

==History==
Aurum Capital Holdings, Incorporated in 2007 owns and operates the website that operates under the name The AurumXchange Company<ref>[https://www.aurumxchange.com/content/privacy The AurumXchange Company - Terms and Conditions]</ref>

The company has been in business exchanging privately since 2007, and publicly since 2009. The company was an official funding partner for MtGox. The company is also an official certified exchanger for PerfectMoney, C-Gold, and VouchX. The company is also certified as the official wholesaler for CosmicPay.

AurumXChange shut down in 2013 after the U.S. government seized assets for [[Liberty Reserve]].

==References==
<references />

==External Links==
* [http://www.runtogold.com/goldmoney/bitgold-review/ Bitgold]

Pecunix

2015-06-17T15:17:43Z

Sunnankar: /* External Links */

{{outdated}}Pecunix is a [[digital currency]] backed by gold. The company holds gold in reserve, and issues currency units denominated in grams of gold (Pecunix GAU).

The payment fee is 0.50% of the payment amount up to 100.00 GAU and 0.15% of any amount over 100.00 GAU to a maximum fee of 3.00 GAU. The fee may be paid by either the buyer or the seller, or the fee may be split 50/50. There is no cost to open or maintain a Pecunix account.

==External Links==
[http://www.pecunix.com Pecunix]
* [http://www.runtogold.com/goldmoney/bitgold-review/ Bitgold]

[[Category:Digital currencies]]

Currency exchange

2015-06-17T15:17:33Z

Sunnankar: /* References */

Bitcoin currency exchanges work in a manner similar to banks. One first deposits amounts of money in the currencies supported by the exchange, to his own account in the exchange, uses these balances to trade with other users of the exchange and then withdraws that money. Unlike over-the-counter transactions, there is no risk of losing money due to people not fulfilling their part of the deal, as long as the exchange itself does not commit fraud or withhold money.

Exchanging is done by placing "buy" or "sell" orders, which the exchange system software then matches with each other. "Buy" orders (or "bids") are offers to buy bitcoins in exchange for another currency at a maximum price-per-bitcoin which is set by the offerer. "Sell" orders (or "asks") are offers to sell bitcoins at a minimum price-per-bitcoin. If the bid price of a buy order is higher than the ask price of a sell order, an exchange can be performed and either the bid order, the sell order or both can be removed from the "order book". Thus, at any given time, there is a price above which there are no more buy orders and a slightly higher price below which there are no more sell orders.

Communication with the Bitcoin currency exchanges is commonly done using a standard web browser, over a secure SSL connection.

The payment methods that are most commonly accepted and used by Bitcoin currency exchanges are:

* Bitcoin transfers
* Liberty Reserve
* Bank wires
* Credit cards

Currencies that can be exchanged with Bitcoins in an automated way include:

* US Dollars
* Euros
* Japanese Yen
* Russian Rubles
* Pound Sterling
* Pecunix Gold

=="Soft currencies" and chargebacks==

Exchanging bitcoins for other forms of currency brings up some issues regarding chargeback fraud. Specifically, payment methods such as credit cards, and PayPal, can be reversed up to 90 days after the transaction took place. In contrast, bitcoin is a "hard currency", once you spend bitcoins, you cannot get them back by 'pulling' from your side. Thus, when you trade bitcoin for a 'soft' currency like paypal or credit card, you open yourself up to the risk of chargeback after you send bitcoin. The buyer may initiate a chargeback by claiming non-receipt of goods, or if a stolen account was used, the real account owner will initiate the process once he notices a charge he didn't make. As a result, it is strongly recommended to not trade 'soft' currency for 'hard' currency with people you do not know or trust.

In January, 2010, an open source currency exchange platform was released by the founder of [[Bitcoin Central]].

The two major exchanges at the time, [[Bitcoin Market]] and [[MtGox]], were hit with a wave of PayPal scams in October 2010, where one or a group of individuals used stolen PayPal accounts to fund their exchange accounts to buy bitcoins. This has caused the freezing of the Mtgox paypal account, and a suspension of new user registration on [[Bitcoin Market]]. These account freezes caused a temporary liquidity problem for the bitcoin economy, as it became more difficult to exchange dollars for bitcoins.

==Exchange Rates and Market Forces==

Early in the life of Bitcoin, the currency showed some major fluctuations in exchange value, ranging from under $50 to $266 US. The exchange rate of Bitcoin has shown relatively stable growth since the beginning of 2013. The current exchange rate for bitcoins is at $959.58 US. The all time high for the value of a single bitcoin was on November 17th, 2013 when it reached $1216.73 US on the Mt. Gox exchange.

Bitcoin has been criticized by economists for bubbling up around itself, similar to the housing market in the US before the crash and it is true that Bitcoin has shown a tendency for rapid rises and crashes in price. However, given the instability of the global economy, Bitcoin has proven to be a reliable investment compared to many other popular currencies. In particular the European debt crisis gave rise to a large amount of currency being converted to bitcoin to keep it safe from the falling value of the Euro. These investments in turn drove up the value of the bitcoin thanks to its unique production method.

Despite the growing popularity of bitcoin transactions and the generally rising price, several events have shown an inability to withstand major blows to its reputation. The FBI seizure of aroun 26,000 bitcoins from the drug distribution website Silk Road more than halved the value of individual bitcoins. Technical errors have also proven to be a difficulty for speculators on the exchange value of the BTC. In April of 2013, a backlog of transactions shut down the Mt. Gox website, causing a drop in value from $266 to $77 US.

While it is becoming easier to acquire, mine<ref>[https://www.bitcoinmining.com Bitcoin Mining]</ref> and spend bitcoins, the availability of access to the currency has been one of the greatest sources of variability in its exchange rate. Because of crackdowns by various governments, most notably the US, it can be difficult to convert your local currency into Bitcoin, which has led to highly variable prices based on geography, which, for a currency which is designed to be borderless, has proven to be an issue, given that so many bitcoin users treat their bitcoins more like an asset than a currency, that is to say, they intend to hold onto their BTC until they decide to convert back into their local currency, rather than spend it online for anonymous transactions.

==See also==

* [[:Category:Exchanges|Exchanges]]
* [[Buying bitcoins]]
* [[Selling bitcoins]]
* [[Secure Trading]]

==References==
<references/>

==External Links==
* [http://www.runtogold.com/goldmoney/bitgold-review/ Bitgold]

[[Category:Exchanges]]

Currency exchange

2015-06-17T15:17:16Z

Sunnankar: /* Exchange Rates and Market Forces */

Bits of Gold

2015-06-17T15:16:02Z

Sunnankar: /* References */

[[File:333.JPG|right]]
A Company registered in Tel-Aviv, Israel which provides ILS/BTC exchange services for a fee.

== Services ==

'''Bits of Gold''' lets its users to send their money from all over the world and exchange it for [[Bitcoin|bitcoins]].

Money forwarding is made through means of regular interbank transfers and can also be expedited through the use of IBAN (העברת זה”ב) transfers.

The company cooperates with [[BitStamp]] for all USD/BTC exchange purposes and with [[MyWallet]] to create wallets for users which don't provide their own ones.

== See also ==

* [[Exchanges]]

== References ==

* [https://www.bitsofgold.co.il/en Bits of Gold website]
* [http://www.runtogold.com/goldmoney/bitgold-review/ Bitgold]

E-gold

2015-06-17T15:15:48Z

Sunnankar: /* See Also */

e-gold is a now defunct gold [[digital currency|digital currencies]] operated by Gold & Silver Reserve Inc. under e-gold Ltd. that allowed the instant transfer of gold ownership between 1996 and 2009, when transfers were suspended due to legal issues. e-gold Ltd. was incorporated in Nevis, Saint Kitts and Nevis with operations conducted out of Florida, USA.

==History==

e-gold was founded in 1996 by Dr. Douglas Jackson and Barry K. Downey.
The number of e-gold accounts (as claimed by e-gold) grew from 1 million in November 2003 to 3 million on 22 April 2006. In 2008, the company reported more than 5 million accounts

In 2007 the US Federal government accused e-gold of money laundering and other crimes and closed down several exchanges. E-gold began to cooperate with prosecutors to monitor transactions, despite this, e-gold itself was then indicted and forced to block all accounts and transfers.

==See Also==
* [[GoldMoney]]
* [[e-bullion]]
* [[Pecunix]]
* [[1mdc]]
* [[e-dinar]]
* [http://www.runtogold.com/goldmoney/bitgold-review/ Bitgold]

==External Links==

* [http://www.e-gold.com/ e-gold] web site
* [http://en.wikipedia.org/wiki/E-gold e-gold] e-gold wikipedia page

[[Category:Digital currencies]]

Bit Gold proposal

2015-06-17T15:15:36Z

Sunnankar: /* References */

Nanaimo Gold

2015-06-17T15:15:02Z

Sunnankar: /* Currency type: */

An operation by Shane Smith, an independent business operator, located in Nanaimo BC Canada.

Bitcoins and other digital currencies may be purchased and sold using any of a number of different payment methods.

==History==

On April 08, 2011 the exchange described the availability of automated trading between bitcoins and oter digital currencies<ref>[http://www.bitcointalk.org/index.php?topic=5555.0 Nanaimo Gold automatic LR <---> BTC service]</ref>.

==Currency type:==
* Bitcoin
* [[Pecunix]]
* c-gold
* HD-Money
* EuroGoldCash
* [http://www.runtogold.com/goldmoney/bitgold-review/ Bitgold]

==Accept payment by:==
* Western Union Money Transfer
* Moneygram International Money Transfer
* Canada Post Money Order [by mail]
* Cash by mail or deposited at a BofA (U.S.) or RBC (Canada) bank.

==See Also==

* [[Buying bitcoins]]
* [[Selling bitcoins]]

==External Links==
* [http://www.nanaimogold.com/ Official website]
* [http://www.nanaimogold.com/bitcoin.php Automated Bitcoin <--> Liberty Reserve exchange]
* [http://www.nanaimogold.com/buy.php Buying digital currency]
* [http://www.nanaimogold.com/sell.php Selling digital currency]

==References==
<references />

[[Category:Exchanges]]

Altcoin

2015-06-17T03:42:49Z

Sunnankar: /* References */ References

{{seealso|List of alternative cryptocurrencies}}
Altcoins are cryptocurrencies other than Bitcoin.
The majority of altcoins are forks of Bitcoin with small uninteresting changes. This page categorises different ways altcoins have modified Bitcoin.

==Different proof-of-work algorithm==

The PoW algorithm used for mining Bitcoin is SHA2.
It was chosen because it is fast to verify and has been critically analyzed.
SHA2 has had ASICs developed for it meaning there is a much smaller risk of centralization.
The following mining algorithms are being used in different altcoins:

*[[Scrypt proof of work]]
*Combination of hashing algorithms in series (e.g. X11)
*Combination of hashing algorithms in parallel (e.g. Myriad algorithm)

The problem with having an algorithm that is "easy to mine with" (referring to the ability to CPU or GPU mine profitably) is that mining should be hard in order to secure the network. When a mining algorithm is difficult to make ASICs for, there is a higher barrier to entry. A high barrier to entry increases the time that the first group to create ASICs will monopolize the market (and the time the network is vulnerable to a 51% attack from a single source). Many argue that the creators or the developers could simply change the mining algorithm when an ASIC is developed, but this defeats the purpose of decentralized consensus by causing centralization.<ref>[https://download.wpsoftware.net/bitcoin/asic-faq.pdf ASIC FAQ]</ref>

If these cryptocurrencies do have a healthy number of companies producing ASICs and have avoided centralization, they still are using algorithms that take longer to verify than SHA2. Therefore, at best a cryptocurrencies with merely a hashing algorithm change are as good as an exact clone of Bitcoin and not better (however since Bitcoin already exists, an exact clone of Bitcoin has no innovation or value). If the hashing algorithm is slower, as most altcoin algorithms are, it is a disadvantage because it takes more processing time to validate a block and increases the number of organic re-orgs (makes it easier to double spend).

==Proof Of Stake==

In [[Proof of Stake]], instead of sacrificing energy to mine a block, a user must prove they own a certain amount of the cryptocurrency to generate a block. The more stake you own, the more likely you are to generate a block. In theory, this should prevent users from creating forks because it will devalue their stake and it should save a lot of energy.

Proof of Stake sounds like a good idea, but ironically, there is the "Nothing at Stake" problem. Because mining Bitcoin is costly, it is not smart to waste your energy on a fork that won't earn you any money, however with Proof of Stake, it is free to mine a fork.

An example of a nothing at stake attack is an attacker buying lots of "old stake" from users inexpensively (inexpensive to users who no longer have stake in the currency). This can be made convenient by offering small payments to users for uploading their wallet.dat. Eventually after accumulating enough "old stake", the user can begin creating blocks and destroying as many or more coin days than the network was at that time. This block generation can be repeated until it catches up to and beats the current main-chain very cheaply.

There are also "stake grinding" attacks which require a trivial amount of currency. In a stake<ref>[https://bitcointalk.org/index.php?topic=131901.0 Peercoin Security Analysis]</ref> grinding attack, the attacker has a small amount of stake and goes through the history of the blockchain and finds places where their stake wins a block. In order to consecutively win, they modify the next block header until some stake they own wins once again. This attack requires a bit of computation, but definately isn't impractical.

Because these attacks exists, including Peercoin<ref>[https://github.com/ppcoin/ppcoin/blob/master/src/checkpoints.cpp#L370 Peercoin Source | Centralized Checkpointing Public Key]</ref> and Blackcoin<ref>[https://github.com/rat4/blackcoin/blob/master/src/checkpoints.cpp#L361 Blackcoin Source | Centralized Checkpointing Public Key]</ref> proof of stake cryptocurrencies have "master" public keys that control the blockchain.

This class of cryptocurrency is either insecure or centralized, however proof of stake (based on a PoW currency) is useful in some systems because gaining stake is costly, but it isn't workable for bootstrapping distributed consensus.

==Application Built on Top of a Cryptocurrency==

Bitcoin is a lot like HTTP. It is an application layer protocol and tools can be built on it (like websites can be built on HTTP). There is a class of cryptocurrencies that promise features like casino websites and exchanges and anonymity protocols to be built on top of them.

When creating a new website, one doesn't make a new protocol unless it is necessary. For example, HTTPS is an encrypted version of HTTP, therefore it is useful and necessary. When creating an app such as "[https://bitcointalk.org/index.php?topic=467857.0 DarkSend]", one doesn't need to make a new protocol such as "Darkcoin". This is synonymous to making an HTTPS alternative (eg. HTTPSX) for your new encrypted chat website and not adding any new security or functionality to HTTPSX.

Because Darkcoin is by far the most popular cryptocurrency of this class, the Darkcoin example will be covered in this section.

The Darkcoin devs created a tool called DarkSend. DarkSend is an implementation of coinjoin (an anonymity feature originally implemented in Bitcoin<ref>[https://bitcointalk.org/index.php?topic=279249.0 Coinjoin Outline | BitcoinTalk]</ref>) which utilizes the Darkcoin network to organize the coinjoins. If DarkSend becomes open source and is useful, it will be ported to Bitcoin with a few small modifications. These changes won't be a hardfork, they will likely involve the masternodes being paid by those they are coinjoining for rather than the block reward, which is already possible and implemented for Bitcoin. <ref>[https://www.wpsoftware.net/coinjoin/ Rotating Coinjoiner]</ref>Currently one must hold 1000DRK to become a DarkSend masternodes. Masternodes are paid 10% of the block reward.<ref>[https://darkcointalk.org/threads/darkcoin-update-masternode-requirements-masternode-payments.225/ DarkSend Payment Scheme]</ref> This is a flawed reward scheme because while purchasing 1000DRK is trustlessly verifiable, a user running a DarkSend masternode isn't trustlessly verifiable. It is also costs bandwidth to run a masternode, therefore there is an incentive to buy 1000DRK and get a chance at the 10% block reward masternodes are being paid, but not actually act as a masternode. For this reason, DarkSend would work better if the masternodes were paid by those they were helping coinjoin, or if there wasn't a masternode at all and everyone collaborated in a decentralized fashion. The better implementation not vulnerable to tragedy of the commons is compatible with Bitcoin, therefore, the Darksend protocol serves no purpose.

==Demographic Based Premined Cryptocurrencies==

This is a new class of altcoin that is targeted at a certain demographic.

All of these cryptocurrencies have a large premine intended to be paid to members of that demographic. Ultimately, all of these coins have suffered (or are suffering) their fate of an immediate sell off after the "airdrop" (term for distribution of coins to the target demographic) begins.

Note: These cryptocurrencies aren't government initiatives, but are independently created for that demographic.

==Useful Cryptocurrencies==

A cryptocurrency is useful if it accomplishes a task that Bitcoin cannot.

*Acting as a keystore for things like decentralized domain registration.
*Having demmurage or some other economic system that is one of the [[prohibited changes]].
*Allowing creation of and transmission of digital assets.

==References==
<references/>

==External References==

* [https://www.weusecoins.com/what-is-litecoin/ What is Litecoin?]
* [https://www.bitcoinmining.com/what-is-litecoin-mining/ What is Litecoin Mining?]
* [https://www.weusecoins.com/what-is-dogecoin/ What is Dogecoin?]
* [https://www.bitcoinmining.com/what-is-dogecoin-mining/ What is Dogecoin Mining?]

Altcoin

2015-06-17T03:42:12Z

Sunnankar: /* References */ References

{{seealso|List of alternative cryptocurrencies}}
Altcoins are cryptocurrencies other than Bitcoin.
The majority of altcoins are forks of Bitcoin with small uninteresting changes. This page categorises different ways altcoins have modified Bitcoin.

==Different proof-of-work algorithm==

The PoW algorithm used for mining Bitcoin is SHA2.
It was chosen because it is fast to verify and has been critically analyzed.
SHA2 has had ASICs developed for it meaning there is a much smaller risk of centralization.
The following mining algorithms are being used in different altcoins:

*[[Scrypt proof of work]]
*Combination of hashing algorithms in series (e.g. X11)
*Combination of hashing algorithms in parallel (e.g. Myriad algorithm)

The problem with having an algorithm that is "easy to mine with" (referring to the ability to CPU or GPU mine profitably) is that mining should be hard in order to secure the network. When a mining algorithm is difficult to make ASICs for, there is a higher barrier to entry. A high barrier to entry increases the time that the first group to create ASICs will monopolize the market (and the time the network is vulnerable to a 51% attack from a single source). Many argue that the creators or the developers could simply change the mining algorithm when an ASIC is developed, but this defeats the purpose of decentralized consensus by causing centralization.<ref>[https://download.wpsoftware.net/bitcoin/asic-faq.pdf ASIC FAQ]</ref>

If these cryptocurrencies do have a healthy number of companies producing ASICs and have avoided centralization, they still are using algorithms that take longer to verify than SHA2. Therefore, at best a cryptocurrencies with merely a hashing algorithm change are as good as an exact clone of Bitcoin and not better (however since Bitcoin already exists, an exact clone of Bitcoin has no innovation or value). If the hashing algorithm is slower, as most altcoin algorithms are, it is a disadvantage because it takes more processing time to validate a block and increases the number of organic re-orgs (makes it easier to double spend).

==Proof Of Stake==

In [[Proof of Stake]], instead of sacrificing energy to mine a block, a user must prove they own a certain amount of the cryptocurrency to generate a block. The more stake you own, the more likely you are to generate a block. In theory, this should prevent users from creating forks because it will devalue their stake and it should save a lot of energy.

Proof of Stake sounds like a good idea, but ironically, there is the "Nothing at Stake" problem. Because mining Bitcoin is costly, it is not smart to waste your energy on a fork that won't earn you any money, however with Proof of Stake, it is free to mine a fork.

An example of a nothing at stake attack is an attacker buying lots of "old stake" from users inexpensively (inexpensive to users who no longer have stake in the currency). This can be made convenient by offering small payments to users for uploading their wallet.dat. Eventually after accumulating enough "old stake", the user can begin creating blocks and destroying as many or more coin days than the network was at that time. This block generation can be repeated until it catches up to and beats the current main-chain very cheaply.

There are also "stake grinding" attacks which require a trivial amount of currency. In a stake<ref>[https://bitcointalk.org/index.php?topic=131901.0 Peercoin Security Analysis]</ref> grinding attack, the attacker has a small amount of stake and goes through the history of the blockchain and finds places where their stake wins a block. In order to consecutively win, they modify the next block header until some stake they own wins once again. This attack requires a bit of computation, but definately isn't impractical.

Because these attacks exists, including Peercoin<ref>[https://github.com/ppcoin/ppcoin/blob/master/src/checkpoints.cpp#L370 Peercoin Source | Centralized Checkpointing Public Key]</ref> and Blackcoin<ref>[https://github.com/rat4/blackcoin/blob/master/src/checkpoints.cpp#L361 Blackcoin Source | Centralized Checkpointing Public Key]</ref> proof of stake cryptocurrencies have "master" public keys that control the blockchain.

This class of cryptocurrency is either insecure or centralized, however proof of stake (based on a PoW currency) is useful in some systems because gaining stake is costly, but it isn't workable for bootstrapping distributed consensus.

==Application Built on Top of a Cryptocurrency==

Bitcoin is a lot like HTTP. It is an application layer protocol and tools can be built on it (like websites can be built on HTTP). There is a class of cryptocurrencies that promise features like casino websites and exchanges and anonymity protocols to be built on top of them.

When creating a new website, one doesn't make a new protocol unless it is necessary. For example, HTTPS is an encrypted version of HTTP, therefore it is useful and necessary. When creating an app such as "[https://bitcointalk.org/index.php?topic=467857.0 DarkSend]", one doesn't need to make a new protocol such as "Darkcoin". This is synonymous to making an HTTPS alternative (eg. HTTPSX) for your new encrypted chat website and not adding any new security or functionality to HTTPSX.

Because Darkcoin is by far the most popular cryptocurrency of this class, the Darkcoin example will be covered in this section.

The Darkcoin devs created a tool called DarkSend. DarkSend is an implementation of coinjoin (an anonymity feature originally implemented in Bitcoin<ref>[https://bitcointalk.org/index.php?topic=279249.0 Coinjoin Outline | BitcoinTalk]</ref>) which utilizes the Darkcoin network to organize the coinjoins. If DarkSend becomes open source and is useful, it will be ported to Bitcoin with a few small modifications. These changes won't be a hardfork, they will likely involve the masternodes being paid by those they are coinjoining for rather than the block reward, which is already possible and implemented for Bitcoin. <ref>[https://www.wpsoftware.net/coinjoin/ Rotating Coinjoiner]</ref>Currently one must hold 1000DRK to become a DarkSend masternodes. Masternodes are paid 10% of the block reward.<ref>[https://darkcointalk.org/threads/darkcoin-update-masternode-requirements-masternode-payments.225/ DarkSend Payment Scheme]</ref> This is a flawed reward scheme because while purchasing 1000DRK is trustlessly verifiable, a user running a DarkSend masternode isn't trustlessly verifiable. It is also costs bandwidth to run a masternode, therefore there is an incentive to buy 1000DRK and get a chance at the 10% block reward masternodes are being paid, but not actually act as a masternode. For this reason, DarkSend would work better if the masternodes were paid by those they were helping coinjoin, or if there wasn't a masternode at all and everyone collaborated in a decentralized fashion. The better implementation not vulnerable to tragedy of the commons is compatible with Bitcoin, therefore, the Darksend protocol serves no purpose.

==Demographic Based Premined Cryptocurrencies==

This is a new class of altcoin that is targeted at a certain demographic.

All of these cryptocurrencies have a large premine intended to be paid to members of that demographic. Ultimately, all of these coins have suffered (or are suffering) their fate of an immediate sell off after the "airdrop" (term for distribution of coins to the target demographic) begins.

Note: These cryptocurrencies aren't government initiatives, but are independently created for that demographic.

==Useful Cryptocurrencies==

A cryptocurrency is useful if it accomplishes a task that Bitcoin cannot.

*Acting as a keystore for things like decentralized domain registration.
*Having demmurage or some other economic system that is one of the [[prohibited changes]].
*Allowing creation of and transmission of digital assets.

==References==
<references/>

* [https://www.weusecoins.com/what-is-litecoin/ What is Litecoin?]
* [https://www.bitcoinmining.com/what-is-litecoin-mining/ What is Litecoin Mining?]

Scrypt proof of work

2015-06-17T03:41:52Z

Sunnankar: /* References */ References

'''Scrypt proof of work''' denotes the [[Hashcash]] proof of work using scrypt as underlying hash function.
By using a memory-intensive hash function designed to reduce the efficiency of logic circuits, this was claimed to make only CPU mining remain profitable, even with the advent of GPU mining, and completely failed in that goal.

It has been less widely used and analyzed than the SHA2 hashing algorithm used in Bitcoin, so there is some concern about possible weaknesses in its cryptographic scheme being discovered in the future.

== History ==
Originally introduced as part of the [[altcoin]] '''Tenebrix''' (TBX) by ArtForz and Lolcust, it was claimed to be resistant to GPU, FPGA, and ASIC implementation.

=== Specialized hardware ===
Around mid-2012, GPU-based scrypt mining began to become widespread, and by late 2013 scrypt ASICs had began shipping. As scrypt is not GPU-resistant, FPGA-resistant nor ASIC-resistant, it has failed to meet its stated goals entirely.

== Problems ==

=== Vulnerability to mining monopoly ===

"51% attacks" become more difficult to launch and maintain as the hash rate of the network grows.
However, this argument posits that since scrypt is designed to be inefficient on all common computer components (both CPUs and GPUs), a malicious entity need only produce a small batch of specialized/custom hardware to overtake all the commodity mining systems combined.

=== Memory bandwidth refutation ===
Some attempt to refute this by arguing that scrypt is not designed to be inefficient, but is instead designed to be highly dependent on memory bandwidth.
Since the high-speed cache RAM on modern processors already takes up most of the die space, no sizeable improvement could then be made by creating custom chips.
If we accept this argument we then estimate the cost of attack utilizing GPUs that are available today.

To do so we start with an estimated cost of hardware at $400 per megahash per second and a reasonable network hashrate of 30 gigahashes per second.
The total amount of equipment necessary to match and takeover this network via 51% attack would then be an estimated $12M USD (or about 45,000 AMD HD 7950s).

== Variations ==

In mid-2013, a user nicknamed pocopoco introduced an altcoin ("YACoin") using scrypt with an adaptive "N-factor"<ref>[https://bitcointalk.org/?topic=196196 BitcoinTalk discussion thread for the "YACoin" altcoin]</ref>.

== References ==
<references/>

* [https://www.weusecoins.com/what-is-litecoin/ What is Litecoin?]
* [https://www.bitcoinmining.com/what-is-litecoin-mining/ What is Litecoin Mining?]

Multi-signature

2015-06-13T16:45:50Z

Sunnankar: /* References */

Multisigniture (multisig) refers to requiring more than one key to authorize a Bitcoin [[transaction]].

Consider the following scenario:<blockquote>Suppose I am working with a company that wants to accept Bitcoin for international trades.

The company, for security reasons, would not want a single one of its employees to have access to the company BTC wallet's password. Any transaction would have to meet the approval of more than one employee.

Is this possible already? If not, how could it be implemented with public-key cryptography?<ref>https://bitcointalk.org/index.php?topic=507297.msg5594085</ref></blockquote>Multisig is the the solution to this.

==Implementations==
Shamir's [https://en.wikipedia.org/wiki/Secret_sharing Secret Sharing] Scheme (ssss)<ref>https://point-at-infinity.org/ssss/</ref> is a general software implementation of multisig.

Specific to Bitcoin, [[GreenAddress|GreenAddress.it]] has 2-of-2 and 2-of-3 accounts (requiring at least two keys to authorize a transaction). [[Coinbase (business)|Coinbase]] also offers 2-of-3 and 3-of-5 multisig, which they call [https://support.coinbase.com/customer/portal/articles/1743782-what-is-the-multisig-vault- Vault].

==Multisigniture Addresses==
<blockquote>A [[Address#Multi-signature_addresses|multi-signature address]] is an address that is associated with more than one ECDSA private key. The simplest type is an m-of-n address - it is associated with n private keys, and sending bitcoins from this address requires signatures from at least m keys. A multi-signature transaction is one that sends funds from a multi-signature address.<ref>https://bitcoin.stackexchange.com/a/3729/4334</ref></blockquote>
===Creating a Multisigniture Address===
A 2of3 multisig address can be created by following these steps:<ref>https://bitcoin.stackexchange.com/a/10593/4334</ref>

<blockquote><ol><li>Gather (or generate) 3 bitcoin addresses, on whichever machines will be participating, using getnewaddress or getaccountaddress RPC commands (or copy and paste from the GUI).</li>
<li>Get their public keys using the <tt>validateaddress</tt> [[API_reference_%28JSON-RPC%29|RPC]] command 3 times.</li>
<li>Then create a 2-of-3 multisig address using addmultisigaddress; e.g.<blockquote><code>bitcoind addmultisigaddress 2 '["044322868cb17d64dcc22185ae2d4493111d73244c3668f8ac79ecc79c0ba8d30a6756d0fa20157 709af3281cc721c7f53321a8cabda29b77900b7e4fe0174b114","..second pubkey..","..third pubkey.."]'</code></blockquote></li></ol><tt>addmultisigaddress</tt> returns the multisignature address. Be a little careful, the public keys are raw hexadecimal and don't contain checksums like bitcoin addresses do. You can then send funds into that 2-of-3 transaction using the normal sendtoaddress/sendmany RPC commands, or the GUI (or anything that's been updated to recognize multisig addresses).<ref>https://bitcointalk.org/index.php?topic=82213.msg906833#msg906833</ref></blockquote>

==History of Multisigniture==
Multisigniture has been used for thousands of years to protect the security of crypts holding precious relics of saints. The superior of a monastery would give monks only partial "keys" for gaining access to the precious relics; the monks would not know they only held a partial key. Thus, no single monk could gain access to and possibly steal the precious relics.

==References==
<references />

* [https://bitcoinmagazine.com/11108/multisig-future-bitcoin/ How To Create A Bitcoin Multisig Wallet]

Contract

2015-06-13T16:44:49Z

Sunnankar: /* Trust minimization: multiple independent oracles */

A '''distributed contract''' is a method of using Bitcoin to form agreements with people via the block chain. Contracts don't make anything possible that was previously impossible, but rather, they allow you to solve common problems in a way that minimizes trust. Minimal trust often makes things more convenient by allowing human judgements to be taken out of the loop, thus allowing complete automation.

By building low trust protocols that interact with Bitcoin, entirely new products can be created:

* [[Smart Property|Smart property]] is property that can be atomically traded and loaned via the block chain.
* [[Transferable virtual property]] are digital items that can be traded but not duplicated.
* [[Agents]] are autonomous programs that maintain their own wallet, which they use to buy server time. Money is obtained by the agent selling services. If demand exceeds supply the agents can spawn children that either survive or die depending on whether they can get enough business.
* [[Distributed markets]] are a way to implement peer to peer bond and stock trading, allowing Bitcoin to be evolve into a full competitor to the international financial system.
* The [[Ripple currency exchange]] is a way to implement a distributed currency exchange based on social networks.

This page also lists some smaller examples.

Many of the ideas underlying Bitcoin contracts were first described by Nick Szabó in his seminal paper,
[http://szabo.best.vwh.net/formalize.html Formalizing and Securing Relationships on Public Networks]. These pages were written by [mailto:mike@plan99.net Mike Hearn]. Contact him if you have an idea for a new type of contract. You can watch '''[https://www.youtube.com/watch?feature=player_embedded&v=mD4L7xDNCmA a video of a talk on contracts]''' that was presented at the Bitcoin 2012 conference in London.

==A warning about the mempool transaction replacement mechanism==

In places this page refers to the ability to use the nSequence field for transaction mempool replacement. This mechanism was disabled in [https://github.com/bitcoin/bitcoin/commit/05454818dc7ed92f577a1a1ef6798049f17a52e7#diff-118fcbaaba162ba17933c7893247df3aR522 2010], and more recently the code has been [https://github.com/bitcoin/bitcoin/commit/98c7c8fd1d3712e02be0e9f2eeca7e02aa54d197 removed completely], due to concerns over people using it to perform DoS attacks. Implementors should take this into account and try to create contract mechanisms that do not rely on mempool replacement if they wish to have their implementations work with current implementations. If Bitcoin changes in future to allow mempool replacement once again, this page will be updated.

==Theory==

Every [[transaction]] in Bitcoin has one or more inputs and outputs. Each input/output has a small, pure function associated with it called a [[script]]. Scripts can contain signatures over simplified forms of the transaction itself.

Every transaction can have a lock time associated with it. This allows the transaction to be pending and replaceable until an agreed-upon future time, specified either as a block index or as a timestamp (the same field is used for both, but values less than 500 million are interpreted as a block index). If a transaction's lock time has been reached, we say it is final.

Each transaction input has a sequence number. In a normal transaction that just moves value around, the sequence numbers are all UINT_MAX and the lock time is zero. If the lock time has not yet been reached, but all the sequence numbers are UINT_MAX, the transaction is also considered final. Sequence numbers can be used to issue new versions of a transaction without invalidating other inputs signatures, e.g., in the case where each input on a transaction comes from a different party, each input may start with a sequence number of zero, and those numbers can be incremented independently.

Signature checking is flexible because the form of transaction that is signed can be controlled through the use of SIGHASH flags, which are stuck on the end of a signature. In this way, contracts can be constructed in which each party signs only a part of it, allowing other parts to be changed without their involvement. The SIGHASH flags have two parts, a mode and the ANYONECANPAY modifier:

# SIGHASH_ALL: This is the default. It indicates that everything about the transaction is signed, except for the input scripts. Signing the input scripts as well would obviously make it impossible to construct a transaction, so they are always blanked out. Note, though, that other properties of the input, like the connected output and sequence numbers, ''are'' signed; it's only the scripts that are not. Intuitively, it means "I agree to put my money in, if everyone puts their money in and the outputs are this".
# SIGHASH_NONE: The outputs are not signed and can be anything. Use this to indicate "I agree to put my money in, as long as everyone puts their money in, but I don't care what's done with the output". This mode allows others to update the transaction by changing their inputs sequence numbers.
# SIGHASH_SINGLE: Like SIGHASH_NONE, the inputs are signed, but the sequence numbers are blanked, so others can create new versions of the transaction. However, the only output that is signed is the one at the same position as the input. Use this to indicate "I agree, as long as my output is what I want; I don't care about the others".

The SIGHASH_ANYONECANPAY modifier can be combined with the above three modes. When set, only that input is signed and the other inputs can be anything.

Scripts can contain the CHECKMULTISIG opcode. This opcode provides n-of-m checking: you provide multiple public keys, and specify the number of valid signatures that must be present. The number of signatures can be less than the number of public keys. An output can require two signatures to be spent by setting it to something like this:

2 <pubkey1> <pubkey2> 2 CHECKMULTISIGVERIFY

There are two general patterns for safely creating contracts:

# Transactions are passed around outside of the P2P network, in partially-complete or invalid forms.
# Two transactions are used: one (the contract) is created and signed but not broadcast right away. Instead, the other transaction (the payment) is broadcast after the contract is agreed to lock in the money, and then the contract is broadcast.

This is to ensure that people always know what they are agreeing to.

Together, these features let us build interesting new financial tools on top of the block chain.

==Example 1: Providing a deposit==

Imagine that you open an account on a website (eg, a forum or wiki) and wish to establish your trustworthiness with the operators, but you don't have any pre-existing reputation to leverage. One solution is to buy trust by paying the website some money. But if at some point you close your account, you'd probably like that money back. You may not trust the site enough to give them a deposit that they are tempted to spend. Another risk is that the site might just disappear one day.

The goal is to prove that you made a sacrifice of some kind so the site knows you're not a spambot, but you don't want them to be able to spend the money. And if the operators disappear, you'd eventually like the coins back without needing anything from them.

We can solve this problem with a contract:

# The user and website send each other a newly-generated public key.
# The user creates transaction Tx1 (the payment) putting 10 BTC into an output that requires both user and website to sign, but does not broadcast it. They use the key from the previous step for the site.
# User sends the hash of Tx1 to the website.
# The website creates a transaction Tx2 (the contract). Tx2 spends Tx1 and pays it back to the user via the address he provided in the first step. Note that Tx1 requires two signatures, so this transaction can't be complete. nLockTime is set to some date in the future (eg, six months). The sequence number on the input is set to zero.
# Finally, the incomplete (half-signed) transaction is sent back to the user. The user checks that the contract is as expected - that the coins will eventually come back to him - but, unless things are changed, only after six months. Because the sequence number is zero, the contract can be amended in future if both parties agree. The script in the input isn't finished though; there are only zeros where the user's signature should be. He fixes that by signing the contract and putting the new signature in the appropriate spot.
# The user broadcasts Tx1, then broadcasts Tx2.

At this stage, the 10 BTC are in a state where neither the user nor the website can spend them independently. After six months, the contract will complete and the user will get the coins back, even if the website disappears.

What if the user wishes to close his account early? The website creates a new version of Tx2 with nLockTime set to zero and the input sequence number set to UINT_MAX, then he re-signs it. The site hands the tx back to the user, who signs it as well. The user then broadcasts the transaction, terminating the contract early and releasing the coins.

What if the six months is nearly up and the user wishes to keep his account? The same thing applies: the contract can be resigned with a newer nLockTime, a sequence number 1 higher than the previous and rebroadcast 2^32 times. No matter what happens, both parties must agree for the contract to change.

Obviously, if the user turns out to be abusive (i.e., a spammer), the website will not allow an early close of the contract. If too much abuse is getting through, the size of the deposit can be raised or the length of the contract can be increased.

==Example 2: Escrow and dispute mediation==

A buyer wants to trade with somebody he doesn't know or trust. In the common case where the transaction goes well, the client doesn't want any third parties involved. If something goes wrong though, he'd like a third party to decide who gets the money - perhaps a professional dispute mediation service. Note that this concept can apply to either buyer or seller. The mediator might request proof of postage from the merchant, for example.

In other words, one wants to lock up some coins so a third party has to agree in order for them to be spent:

# Agree with the merchant on a dispute mediator (e.g., ClearCoin).
# Ask the merchant for a public key (K1). Ask the mediator for a public key (K2). Create a new key for yourself (K3).
# Send the merchant K2. The merchant challenges the mediator with a random nonce. The mediator signs the nonce with the private form of K2, thus proving it really belongs to merchant.
# Create a transaction (Tx1) with an output script as follows and broadcast it:

2 <K1> <K2> <K3> 3 CHECKMULTISIGVERIFY

Now the coins are locked in such a way that they can only be spent by the following methods:

# Client and the merchant agree (either a successful trade, or merchant agrees to reimburse client without mediation)
# Client and the mediator agree (failed trade, mediator sides with client, like a charge-back)
# The mediator and the merchant agree (goods delivered, merchant gets client's coins despite the dispute)

When signing an input, the contents are set to the connected output. Thus, to redeem this transaction, the client creates a scriptSig containing zeros where the other signature should be, signs it, and then sets one of the slots to his new signature. The partially-complete transaction can then be sent to the merchant or mediator for the second signature.

==Example 3: Assurance contracts==

An [http://en.wikipedia.org/wiki/Assurance_contract assurance contract] is a way of funding the creation of a [http://www.auburn.edu/~johnspm/gloss/public_goods public good], that is, a good that, once created, anyone can benefit from for free. The standard example is a lighthouse: whilst everyone may agree that one should be built, it’s too expensive for an individual sailor to justify building one, given that it will also benefit all his competitors.

One solution is for everyone to pledge money towards the creation of the public good, such that the pledges are only committed if the total value of all pledges is above the cost of creation. If not enough people contribute, nobody has to pay anything.

Examples where Bitcoin is superior to traditional payment methods for assurance contract fundraising include applications where frequent, small pledges need to be made automatically, for instance internet radio station funding and [https://bitcointalk.org/index.php?topic=67255.msg788110#msg788110 web page translation]. Consider a browser extension that you send a bit of money to. It detects the current language of the page and broadcasts a pledge for a translation into your language to be prepared. If enough users with the extension land on the same page at the same time (eg, it was linked to from somewhere high traffic), then enough pledges are broadcast to trigger a payment to a company who prepares a high quality translation. When complete it automatically loads in your browser.

We can model this in Bitcoin as follows:

# An entrepreneur creates a new address and announces that the good will be created if at least 1000 BTC is raised. Anyone can contribute.
# Each party wishing to pledge creates a new transaction spending some of their coins to the announced address, but they do not broadcast it. The transaction is similar to a regular transaction except for three differences: Firstly, there cannot be any change. If you don’t have any outputs of the right size, you must create one first by spending to one of your own addresses. Secondly, the input script signature is signed with SIGHASH_ALL | SIGHASH_ANYONECANPAY. Finally, the output value is set to 1000 BTC. Note that this is not a valid transaction because the output value is larger than the input value.
# The transaction is uploaded to the entrepreneur's server, which saves it to disk and updates its count of how many coins have been pledged.
# Once the server has enough coins, it merges the separate transactions together into a new transaction. The new transaction has a single output that simply spends to the announced address - it is the same as the outputs on each contributed transaction. The inputs to the transaction are collected from the contributed pledges.
# The finished transaction is broadcast, sending the pledged coins to the announced address.

This scheme relies on several aspects of the protocol. The first is the SIGHASH flags used. SIGHASH_ALL is the default and means the entire contents of the transaction are signed, except for the input scripts. SIGHASH_ANYONECANPAY is an additional modifier that means the signature only covers the input it’s found in - the other inputs are not signed and thus can be anything.

By combining these flags together, we are able to create a signature that is valid even when other inputs are added, but breaks if the outputs or other properties of the transaction are changed.

The second aspect we exploit is the fact that a transaction in which the output values are larger than the input values is invalid (for obvious reasons). This means it’s safe to send the entrepreneur a transaction that spends such coins - it’s impossible for him to claim the coins unless he has other inputs that sum to the output value or more.

It's possible to create assurance contracts without using SIGHASH_ANYONECANPAY. Instead, a two step process is used in which pledges are collected without transactions, and once the total value is reached, a transaction with an input for each pledger is created and passed around until all signatures are collected. However, using SIGHASH_ANYONECANPAY and then merging is probably more convenient.

An assurance contract can be prepared for '''[[Funding network security|funding network security]]''' for the next block. In this way, mining can be funded even if block space is not scarce.

An elaboration of this concept is described by Tabarrok in his paper, [http://mason.gmu.edu/~atabarro/PrivateProvision.pdf “The private provision of public goods via dominant assurance contracts”]. In a dominant assurance contract, if a contract fails (not enough pledges within a set time window) the entrepreneur pays a fee to those who pledged so far. This type of contract attempts to arrange incentives such that taking part is always the right strategy. [[Dominant Assurance Contracts|A scheme for dominant assurance contracts]] in Bitcoin has been proposed.

==Example 4: Using external state==

Scripts are, by design, pure functions. They cannot poll external servers or import any state that may change as it would allow an attacker to outrun the block chain. What's more, the scripting language is extremely limited in what it can do. Fortunately, we can make transactions connected to the world in other ways.

Consider the example of an old man who wishes to give an inheritance to his grandson, either on the grandson's 18th birthday or when the man dies, whichever comes first.

To solve this, the man first sends the amount of the inheritance to himself so there is a single output of the right amount. Then he creates a transaction with a lock time of the grandson's 18th birthday that pays the coins to another key owned by the grandson, signs it, and gives it to him - but does not broadcast it. This takes care of the 18th birthday condition. If the date passes, the grandson broadcasts the transaction and claims the coins. He could do it before then, but it doesn't let him get the coins any earlier, and some nodes may choose to drop transactions in the memory pool with lock times far in the future.

The death condition is harder. As Bitcoin nodes cannot measure arbitrary conditions, we must rely on an ''oracle''. An oracle is a server that has a keypair, and signs transactions on request when a user-provided expression evaluates to true.

Here is an example. The man creates a transaction spending his output, and sets the output to:

<hash> OP_DROP 2 <sons pubkey> <oracle pubkey> CHECKMULTISIG

This is the oracle script. It has an unusual form - it pushes data to the stack then immediately deletes it again. The pubkey is published on the oracle's website and is well-known. The hash is set to be the hash of the user-provided expression stating that he has died, written in a form the oracle knows how to evaluate. For example, it could be the hash of the string:

if (has_died('john smith', born_on=1950/01/02)) return (10.0, 1JxgRXEHBi86zYzHN2U4KMyRCg4LvwNUrp);

This little language is hypothetical, it'd be defined by the oracle and could be anything. The return value is an output: an amount of value and an address owned by the grandson.

Once more, the man creates this transaction but gives it directly to his grandson instead of broadcasting it. He also provides the expression that is hashed into the transaction and the name of the oracle that can unlock it.

It is used in the following algorithm:

# The oracle accepts a measurement request. The request contains the user-provided expression, a copy of the output script, and a partially complete transaction provided by the user. Everything in this transaction is finished except for the scriptSig, which contains just one signature (the grandson's) - not enough to unlock the output.
# The oracle checks the user-provided expression hashes to the value in the provided output script. If it doesn't, it returns an error.
# The oracle evaluates the expression. If the result is not the destination address of the output, it returns an error.
# Otherwise the oracle signs the transaction and returns the signature to the user. Note that when signing a Bitcoin transaction, the input script is set to the connected output script. The reason is that when OP_CHECKSIG runs, the script containing the opcode is put in the input being evaluated, _not_ the script containing the signature itself. The oracle has never seen the full output it is being asked to sign, but it doesn't have to. It knows the output script, its own public key, and the hash of the user-provided expression, which is everything it needs to check the output script and finish the transaction.
# The user accepts the new signature, inserts it into the scriptSig and broadcasts the transaction.

If, and only if, the oracle agrees that the man is dead, the grandson can broadcast the two transactions (the contract and the claim) and take the coins.

Oracles can potentially evaluate anything, yet the output script form in the block chain can always be the same. Consider the following possibilities:

today() == 2011/09/25 && exchange_rate(mtgoxUSD) >= 12.5 && exchange_rate(mtgoxUSD) <= 13.5
Require exchange rate to be between two values on a given date

google_results_count(site:www.google.com/hostednews 'Mike Hearn' olympic gold medal) > 0
A bet on me doing something that I will never actually do

// Choose between one of two winners of a bet on the outcome of the Eurovision song contest.
if (eurovision_winner() == 'Azerbaijan')
return 1Lj9udBVDwptFffGSJSC2sohCfudQgSTPD;
else
return 1JxgRXEHBi86zYzHN2U4KMyRCg4LvwNUrp;

The conditions that control whether the oracle signs can be arbitrarily complex, but the block chain never needs to contain more than a single hash.

The [http://earlytemple.com/ ''Early Temple'' project] has implemented a prototype of an oracle that looks for a key phrase in a web page.

===Trust minimization: challenges===

There are various ways to reduce the level of required trust in the oracle.

Going back to our first example, the oracle has not seen the transaction the grandson is trying to unlock, as it was never broadcast, thus, it cannot hold the grandson to ransom because it does not know whether the transaction it's signing for even exists. People can, and should, regularly '''challenge''' the oracle in an automated fashion to ensure it always outputs what is expected. The challenges can be done without spending any coins because the tx to be signed can be invalid (ie, connected to transactions that don't exist). The oracle has no way to know whether a request to be signed is random or real. How to challenge the oracle with conditions that are not yet true is however an open research question.

===Trust minimization: multiple independent oracles===

The number of keys in the CHECKMULTISIG can be increased to allow for '''n-of-m''' oracles if need be. Of course, it is vital to check that the oracles really are independent and not in collusion. An implementation of such a system, and explanation was published in the '''[http://github.com/orisi/wiki/wiki/Orisi-White-Paper Orisi whitepaper]'''.

The idea, in short, is that independent oracles could be run by a set of trustworthy independent actors. Contract participants would first settle upon a set of oracles they both are comfortable using - for example by trusting [http://oracles.lo/ a dedicated site] - and then sign a contract requiring most of the oracles signatures to resolve.

One of the interesting properties of such a system is that it can possibly implement very complicated sets of scripts and external inputs, while being based on a set of standard bitcoin scripts. Another property is that the oracles can possibly replace each ones by forwarding the funds to new [https://bitcoinmagazine.com/11108/multisig-future-bitcoin/ multisig addresses] when they discover that one of the oracles is faulty/corrupted. Finally, such oracles could be used to implement sidechains without dedicated blockchain opcodes.

===Trust minimization: trusted hardware===

Using commodity hardware, you can use '''trusted computing''' in the form of Intel TXT or the AMD equivalent (SKINIT) to set up a sealed hardware environment and then use the TPM chip to attest that fact to a third party. That third party can verify the hardware was in the required state. Defeating this requires someone to be able to interfere with the execution of a program that may run entirely on the CPU, even in extreme cases without any data traversing the memory bus (you can run entirely using on-die cache if the program is small enough).

===Trust minimization: Amazon AWS oracles===

Finally, perhaps the most practical approach currently is to use Amazon Web Services. As of November 2013, the closest we have to a working oracle is [https://bitcointalk.org/index.php?topic=301538.0 this recipe for creating a trusted computing environment using AWS], built in support of [https://bitcointalk.org/index.php?topic=173220.0 this project for doing selective SSL logging and decryption]. The idea is that an oracle, which can be proven trustworthy using the Amazon APIs with Amazon as the root of trust, records encrypted SSL sessions to an online banking interface in such a way that later if there is a dispute about a person-to-person exchange, the logs can be decrypted and the dispute settled.

==Example 5: Trading across chains==

The Bitcoin technology can be adapted to create [[Alternative chain|multiple, independent currencies]]. NameCoin is an example of one such currency that operates under a slightly different set of rules, and can also be used to rent names in a namespace. Currencies that implement the same ideas as Bitcoin can be traded freely against each other with limited trust.

For example, imagine a consortium of companies that issue EURcoins, a crypto-currency that is backed 1:1 by deposits in the consortium's bank accounts. Such a currency would have a different set of tradeoffs to Bitcoin: more centralized, but without FX risk. People might wish to trade Bitcoins for EURcoins back and forth, with the companies only getting involved when cashing in/out of the regular banking system.

To implement this, a [https://bitcointalk.org/index.php?topic=193281.msg2224949#msg2224949 protocol proposed by TierNolan] can be used:

# Party 'A' generates some random data, x (the secret).
# Party 'A' generates Tx1 (the payment) containing an output with the chain-trade script in it. See below for this script and a discussion of it. It allows coin release either by signing with the two keys (key 'A' and key 'B') or with (secret 'x', key 'B'). This transaction is not broadcast. The chain release script contains hashes, not the actual secrets themselves.
# Party 'A' generates Tx2 (the contract), which spends Tx1 and has an output going back to key 'A'. It has a lock time in the future and the input has a sequence number of zero, so it can be replaced. 'A' signs Tx2 and sends it to 'B', who also signs it and sends it back.
# 'A' broadcasts Tx1 and Tx2. Party 'B' can now see the coins but cannot spend them because it does not have an output going to him, and the tx is not finalized anyway.
# 'B' performs the same scheme in reverse on the alternative chain. The lock time for 'B' should be much larger than the lock time for 'A'. Both sides of the trade are now pending but incomplete.
# Since 'A' knows the secret, 'A' can claim his coins immediately. However, 'A', in the process of claiming his coin, reveals the secret 'x' to 'B', who then uses it to finish the other side of the trade with ('x', key 'B').

This protocol makes it feasible to do trades automatically in an entirely peer-to-peer manner, which should ensure good liquidity.

The chain-trade script could look like this:

IF
2 <key A> <key B> 2 CHECKMULTISIGVERIFY
ELSE
<key B> CHECKSIGVERIFY SHA256 <hash of secret x> EQUALVERIFY
ENDIF

The contract input script looks like either:

<sig A> <sig B> 1

or

<secret x> <sig B> 0

i.e., the first data element selects which phase is being used.

See [[Atomic cross-chain trading]] for details.

Note that whilst EURcoins is a natural idea, there are other ways to implement peer-to-peer currency exchange (Bitcoin to fiat and vice versa), see the [[Ripple currency exchange]] article for more information.

Sergio Demian-Lerner proposed [https://bitcointalk.org/index.php?topic=91843.0 P2PTradeX], a solution requiring the validation rules for one blockchain to be effectively encoded into the validation rules for the other.

==Example 6: Pay-for-proof contracts: buying a solution to any pure function==

In example 4, we saw how to make payments conditional on the output of some arbitrary program. Those programs are very powerful and can do anything a regular program can do, like fetching web pages. The downside is that a third party is required (an oracle). Although there are techniques that can help reduce the trust needed in the oracle, none can reduce it to zero.

For a restricted class of programs, pure functions, new cryptographic techniques are starting to become available that can actually reduce the trust needed all the way to zero with no third parties. These programs cannot perform any I/O, but in many cases this restriction turns out to be unimportant or can be worked around in other ways, like by giving the program a signed/timestamped document as an input instead of having the program download it.

Gregory Maxwell has invented a protocol for doing this, which you can read about here: [[Zero Knowledge Contingent Payment]]

==Example 7: Rapidly-adjusted (micro)payments to a pre-determined party==

Bitcoin transactions are very cheap relative to traditional payment systems, but still have a cost due to the need for it to be mined and stored. There are some cases in which you want to rapidly and cheaply adjust the amount of money sent to a particular recipient without incurring the cost of a broadcast transaction.

For example, consider an untrusted internet access point, like a WiFi hotspot in a cafe you never visited before. You'd like to pay 0.001 BTC per 10 kilobytes of usage, without opening an account with the cafe. A zero-trust solution means it could be fully automatic, so you could just pre-allocate a budget on your phone's mobile wallet at the start of the month, and then your device automatically negotiates and pays for internet access on demand. The cafe also wants to allow anyone to pay them without the fear of being ripped off.

To do this, the following protocol can be used. This protocol relies upon a '''different''' behavior of nLockTime to the original design. Starting around 2013 time-locked transactions were made non standard and no longer enter the memory pool, thus cannot be broadcast before the timelock expires. When the behaviour of nLockTime is restored to the original design from Satoshi, a variant of this protocol is required which is discussed below.

We define the client to be the party sending value, and the server to be the party receiving it. This is written from the clients perspective.

# Create a public key (K1). Request a public key from the server (K2).
# Create and sign but do not broadcast a transaction (T1) that sets up a payment of (for example) 10 BTC to an output requiring both the server's private key and one of your own to be used. A good way to do this is use OP_CHECKMULTISIG. The value to be used is chosen as an efficiency tradeoff.
# Create a refund transaction (T2) that is connected to the output of T1 which sends all the money back to yourself. It has a time lock set for some time in the future, for instance a few hours. Don't sign it, and provide the unsigned transaction to the server. By convention, the output script is "2 K1 K2 2 CHECKMULTISIG"
# The server signs T2 using its private key associated with K2 and returns the signature to the client. Note that it has not seen T1 at this point, just the hash (which is in the unsigned T2).
# The client verifies the servers signature is correct and aborts if not.
# The client signs T1 and passes the signature to the server, which now broadcasts the transaction (either party can do this if they both have connectivity). This locks in the money.
# The client then creates a new transaction, T3, which connects to T1 like the refund transaction does and has two outputs. One goes to K1 and the other goes to K2. It starts out with all value allocated to the first output (K1), ie, it does the same thing as the refund transaction but is not time locked. The client signs T3 and provides the transaction and signature to the server.
# The server verifies the output to itself is of the expected size and verifies the client's provided signature is correct.
# When the client wishes to pay the server, it adjusts its copy of T3 to allocate more value to the server's output and less to its own. It then re-signs the new T3 and sends the signature to the server. It does not have to send the whole transaction, just the signature and the amount to increment by is sufficient. The server adjusts its copy of T3 to match the new amounts, verifies the signature and continues.

This continues until the session ends, or the 1-day period is getting close to expiry. The AP then signs and broadcasts the last transaction it saw, allocating the final amount to itself. The refund transaction is needed to handle the case where the server disappears or halts at any point, leaving the allocated value in limbo. If this happens then once the time lock has expired the client can broadcast the refund transaction and get back all the money.

This protocol has [https://code.google.com/p/bitcoinj/wiki/WorkingWithMicropayments been implemented in bitcoinj].

When nLockTime'd transactions are able to enter the memory pool (once more) and transaction replacement has been re-enabled, a variant on the protocol must be used. In this case, no refund transaction is used. Instead each T3 has a sequence number one higher than the previous and all T3's have a time lock set to the same period as above. Each time a payment is made the sequence number is incremented, ensuring that the last version will take precedence. If the channel protocol is not closed cleanly, this means the value transfer won't commit until the time lock expires. To avoid this both parties can cooperate by signing a T3 that has a sequence number of 0xFFFFFFFF resulting in immediate confirmation regardless of the value of nLockTime.

The lock time and sequence numbers avoid an attack in which the AP provides connectivity, and then the user [[double-spending|double-spends]] the output back to themselves using the first version of TX2, thus preventing the cafe from claiming the bill. If the user does try this, the TX won't be included right away, giving the access point a window of time in which it can observe the TX broadcast, and then broadcast the last version it saw, overriding the user's attempted double-spend.

The latter protocol that relies on transaction replacement is more flexible because it allows the value allocated to go down as well as up during the lifetime of the channel as long as the client receives signatures from the server, but for many use cases this functionality is not required. Replacement also allows for more complex configurations of channels that involve more than two parties. Elaboration on such use cases is a left as an exercise for the reader.

==Example 8: Multi-party decentralised lotteries==

Using some of the techniques from example 6 and some very advanced scripting, it becomes possible to build a multi-party lottery with no operator. The exact protocol used is explained in the paper [http://eprint.iacr.org/2013/784 "Secure multiparty computations on Bitcoin"]. A shorter explanation of how it works may be added to this wiki at some point in the future.

==See Also==

* [[Script]]

[[Category:Technical]]

Blockstream Green

2015-06-13T16:43:09Z

Sunnankar: /* Links */

{{advert}}
==Wallet Features==

* Open source clients for both desktop and mobile
* [[Deterministic wallet | HD]]/BIP0032
* Per-transaction 2FA via [[multisignature]], of 4 different kinds: email, sms, robot call, Google Authenticator
* 2-of-2 [[multisignature|multisig]] accounts: Create accounts that can take advantage of GreenAddress' trusted-third-party instant confirmations. Account recovery without access to GreenAddress is achieved with pre-generated [[nLockTime]] transactions (which must be received, typically via email, from GreenAddress on a regular basis).
* 2-of-3 [[multisignature|multisig]] accounts: Create accounts that allow you to access your funds at any time even without access to GreenAddress, using an additional offline recovery key (which only needs to be saved once).
* Transaction information within 2FA message
* BIP0039 mnemonics
* Receive or Send/Tip password protected Bitcoins with BIP0038 (Facebook, Email, Reddit)
* Never reuses the same address which improves both privacy and security
* Easy to use, fast and convenient

==More==

* Great customer support, fast turn around via email, twitter, facebook or reddit

* No practice of any reserve mechanism

* testnet/uat service

* GreenAddress' can't take your funds

* detailed transaction logging, real-time on-screen alerts as funds are received

====Links====

* [http://www.expresscoin.com/wallets/bitcoin/greenaddress How to Setup a GreenAddress Bitcoin Wallet]

* [https://bitcoinmagazine.com/11108/multisig-future-bitcoin/ How To Create A Bitcoin Multisig Wallet]

* [https://play.google.com/store/apps/details?id=it.greenaddress.cordova Android Google Play]

* [https://f-droid.org/repository/browse/?fdfilter=greenaddress&fdid=it.greenaddress.cordova F-Droid Open Source Repo]

* [https://itunes.apple.com/us/app/greenaddress/id889740745 iTunes App Store for iOS]

* [https://chrome.google.com/webstore/detail/greenaddressit/dgbimgjoijjemhdamicmljbncacfndmp Chrome Store]

* [https://github.com/greenaddress/WalletCrx/archive/master.zip Chrome zip for Github (developer mode necessary)]

* [https://greenaddress.it Home]

* [http://blog.greenaddress.it Blog]

* [https://greenaddress.it/faq FAQ]

* [https://greenaddress.it/about About]

* [https://www.youtube.com/watch?v=4PsRUT5oTVU Infographics]

* [https://github.com/greenaddress/ Github]

* [https://reddit.com/r/greenaddress Reddit]

* [https://www.facebook.com/GreenAddressIT Faceboook]

* [https://twitter.com/GreenAddress Twitter]

* [https://test.greenaddress.it Testnet]

[[Category:Wallets]]
[[Category:EWallets]]
[[Category:HybridEWallets]]
[[Category:Services]]
[[Category:Frontends]]
[[Category:Clients]]
[[Category:Mobile]]
[[Category:Cryptobanks]]
[[Category:Bitcoin payment systems]]

Coinb.in

2015-06-13T16:42:51Z

Sunnankar: /* External links */

'''Coinb.in''' is a free and ''open source project'' released under the MIT license, originally by [https://bitcointalk.org/index.php?action=profile;u=34834 OutCast3k] in 2013.

Github: https://github.com/OutCast3k/coinbin/

TOR: 4zpinp6gdkjfplhk.onion

==Features==

* Offline Compressed & uncompressed Address creation.
* Offline [[Address#Multi-signature_addresses|Multisignature Address]] creation.
* [[Deterministic_wallet|HD]] (bip32) support
* "In browser" Key (re)generation.
* Send and receive payments.
* Ability to decode transactions, redeem scripts and more offline.
* Build custom transactions offline.
* Sign transactions offline.
* Signatures are deterministic as per RFC 6979 (https://tools.ietf.org/html/rfc6979#section-3.2)
* Broadcast transactions.
* nLockTime support.
* Add custom data to transactions with the use of OP_RETURN.
* Support current Dark Wallet Stealth Address structure (as of version Alpha 7) for outputs.
* [[Brainwallet|Brain wallet]] support.
* Compatible with bitcoin-qt
* An offical .onion address for tor users.
* Offline qrcode creator and scanning tool

==Privacy==
Coinb.in believes strongly in privacy, not only does it support the use of TOR, the site also does not collect and store IP or transaction data via their servers.

==External links==
* [https://www.coinb.in Coinb.in website]
* [https://bitcoinmagazine.com/11108/multisig-future-bitcoin/ How To Create A Bitcoin Multisig Wallet]

[[Category:eWallets]]
[[Category:Wallets]]
[[Category:HD Wallet]]
[[Category:Multisig]]
[[Category:Services]]
[[Category:Shopping_Cart_Interfaces]]

CEX.IO

2015-06-13T16:38:55Z

Sunnankar: /* References */

{{infobox company|name=CEX.IO|image=[[File:CEX_Logo.png|225px]]
|trading_name=CEX.IO
|industry=[[Exchange|Bitcoin exchange]]
|foundation=July, 2013
|pairs=GHS/BTC GHS/USD BTC/USD BTC/EUR
|website=https://cex.io
}}

==CEX.IO==

'''CEX.IO''' is a multi-functional platform, which embodies Bitcoin crypto exchange and the leading [[cloud mining]] service.

==History==

CEX.IO project development started in early 2013 and proceeded with launching the CEX.IO domain, acquiring assets of [[GHash.IO]] and, finally, registering a legal company CEX.IO LTD in November 2013. By this time, according to [[Blockchain.info]], GHash.IO has become the biggest mining pool, reaching over 42% of the overall Bitcoin mining power, which embodied the 51% attack threat. However, CEX.IO made an official statement, assuring the Bitcoin community that it would “take all necessary precautions to prevent reaching 51% of all hashing power, in order to maintain stability of the Bitcoin network.” In April 2014, CEX.IO user base exceeded 200,000 users. May 2014, CEX.IO imposed trade fee onto the exchange, lowered maintenance costs for cloud-based GHS and added IXC/BTC trading pair. On September 22, 2014, CEX.IO announced the successful launch of the first fiat currency — US dollars are accepted via bank transfer and payment cards. This upgrade allows users to trade Bitcoins and cloud-based hashing power (GHS) as well as deposit and withdraw funds at one place without using services of another exchange. On September 29, 2014, CEX.IO established the second fiat currency, the Euro, which can be bought and sold on the exchange for Bitcoins, Litecoins and Dogecoins.

==GHS Trading==

CEX.IO platform allows users to trade GHS. GHS (gigahash per second) = 1 000 000 000 hashes per second. The speed of mining is measured in hashes per second — the smallest amount of work done by a miner. While mining is more or less passive way of gaining bitcoins, trading GHS allows you to be involved in the world trading processes and enjoy the fruits of your own activity on the Bitcoin commodity exchange. GHS price depends on the correlation between market supply and demand. After purchasing GHS at CEX.IO, users automatically start mining blocks of Bitcoins. CEX.IO is the only Bitcoin commodity exchange where trading and mining can be done simultaneously: even when you decide to sell your GHS, they will still be mining BTC until the moment they are sold. This means your GHS will be making profit for you till the last minute you own them.

==Cloud Mining==

Due to the shared credentials between CEX.IO and [[GHash.IO]] mining pool, users can trade GHS and mine Bitcoins simultaneously. [[Cloud Mining]] is a concept of buying hash power from the pool or hardware operator, where the joint efforts are rewarded with possibly greater income, compared to individual mining with personal hardware. In case of cloud mining, all Bitcoin mining is done in the cloud mining operator data center facility, and once a block is mined, users receive payouts according to their shares via [[PPLNS]]. Apart from mining Bitcoins, users can [[Alternative chain|simultaneously mine]] alternative cryptocurrencies, such as [[NMC]], [[DVC]] and IXC.

With Bitcoin cloud mining users can forget about the most frequent mining problems, such as:
* Electricity consumption
* Connectivity issues
* The need to provide cooling and space
* Noise
* Other hardware maintaining issues

==Trading Pairs==

At CEX.IO, users are able to trade:

USD Market
*BTC/USD
*GHS/USD
*LTC/USD
*DOGE/USD
*DRK/USD

EUR Market
*BTC/EUR
*LTC/EUR
*DOGE/EUR

BTC Market
*GHS BTC
*LTC/BTC
*DOGE/BTC
*DRK/BTC
*NMC/BTC
*WDC/BTC
*FTC/BTC
*USDe/BTC
*MYR/BTC
*POT/BTC
*MEC/BTC
*IXC/BTC
*AUR/BTC
*ANC/BTC
*DGB/BTC

LTC Market

*DOGE/LTC
*FTC/LTC
*ANC/LTC
*WDC/LTC
*DRK/LTC
*MEC/LTC
*GHS/LTC

==Fiat Currencies==

As of September 22, 2014, CEX.IO accepts US dollars via bank transfer and payment cards. Users can trade Bitcoins and cloud-based hashing power (GHS) as well as deposit and withdraw funds at one place without using services of another exchange. The upgrade requires users to verify their identity as part of the company’s KYC policy. CEX.IO plans to continue expanding the range of trading pairs. On September 29, 2014, CEX.IO introduced the second fiat currency, EUR, which can be bought and sold for Bitcoins, Litecoins and Dogecoins. The selection of the second fiat currency was influenced by the high potential of the EU market and the increasing interest of EU citizens in the cryptocurrencies.

==Referral Program==

CEX.IO has a special referral program<ref>[https://cex.io/ref CEX.IO Referral Program]</ref>, according to which users can
introduce new people to the platform and receive 3% of the referred ones’ GHS balance to their bonus account.

==Two-Factor Authentication==

Users can secure their accounts with passwords, but CEX.IO strongly recommends using Two-Factor Authentication (2FA).

Users are free to choose from two 2FA applications: Google Authenticator<ref>[http://en.wikipedia.org/wiki/Google_Authenticator Google Authenticator on Wikipedia]</ref> or [http://authy.com/ Authy]. Alternatively, users can use simple cell phones and get a text or an audio message containing respective authorization code.

==External links==

*[http://cex.io CEX.IO website]
*[http://ghash.io Ghash.IO website]
*[https://www.facebook.com/pages/CEX.IO CEX.IO Facebook]
*[https://twitter.com/cex_io CEX.IO Twitter]

==References==
<references />

* [https://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ Bitcoin Cloud Mining]

[[Category:Exchanges]]
[[Category:Mining_contractors]]

CoinTerra

2015-06-13T16:38:34Z

Sunnankar: /* References */

{{Infobox company|name=CoinTerra, Inc.|image=[[{{ns:file}}:Logo-cointerra.png|270x64px]]|website=http://cointerra.com/}}

CoinTerra™ designs and produces best-in-class Bitcoin mining ASIC processors and systems. Our state-of-the-art design methodologies and advanced architectures enable us to deliver Bitcoin mining solutions with the highest performance ASICs for the lowest power and die area. We are proud to lead the retail bitcoin mining market with our new GoldStrike™ I ASIC and our 2TH/s TerraMiner™ IV Bitcoin miner rigs – both representing the highest performance Bitcoin miner hardware that are currently announced.

== Chapter 7 Bankruptcy ==
On Jan 24, 2015, CoinTerra filed a petition for chapter 7 bankruptcy protection in the United States Bankruptcy Court for the Western District of Texas Austin Division (Case #: 1:15-bk-10109). Further information can be found at the Court's website. http://www.txwb.uscourts.gov/node/19 <ref>http://cointerra.com/wp-content/uploads/2015/01/CoinTerraBG71.png</ref>

== References ==
<references />
* [https://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ Cloud Mining Contract Reviews]

CloudHashing

2015-06-13T16:38:08Z

Sunnankar: /* External Links */

'''CloudHashing''' is a company that sells [[Cloud Mining|bitcoin mining contracts]]. It was founded by Emmanuel Abiodun and is located in Iceland<ref>[http://www.theverge.com/2013/12/23/5238128/inside-a-4-million-icelandic-bitcoin-mining-consortium Inside a $4 million Icelandic bitcoin-mining consortium]</ref>.

==External Links==
* [https://cloudhashing.com/ Official website]
* [https://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ Cloud Mining Contract Reviews]

==References==
<references />

Cloud mining

2015-06-13T16:37:45Z

Sunnankar: /* Cloud Mining Providers */

'''Cloud Mining''' is the process of mining utilizing a remote datacenter with shared processing power often contracted through a Cloud Mining company. This type of mining allows users to mine Bitcoins without having to manage their own hardware. Since Cloud Mining is provided as a service there is generally some cost, and this can result in lower returns for the miner.

==Types of Hosting==

Users of hosted Mining equipment can either lease a physical mining server or a Virtual private server and install mining software on the machine. Instead of leasing a dedicated server, some services offer hashing power hosted in data centers for sale denominated in Gigahash/seconds (GH/s). Users either select a desired amount of hashing power and a period for the contract or in some cases can trade their hashing power.

==Cloud Mining Providers==

Started by [[CEX.IO]] as the first cloud mining company in October 2013, [https://www.bitcoinmining.com/best-bitcoin-cloud-mining-contract-reviews/ cloud mining service] is now provided by such companies as [[CloudHashing]], [[PBmining]], [[Genesis Mining]], [[Cointerra]] and others.