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All About Bitcoin Mining: Road To Riches Or Fool's Gold?

FPGA- And ASIC-Based Mining Devices

FPGA-Based Mining Devices

In late 2011 and early 2012, innovative companies like Butterfly Labs, ZTEX in Germany, a grad student in China, and some individuals in the U.S. started offering FPGA-based mining devices. While most of these were based on the $100 Xilinx Spartan6-150 FPGA, the BFL design used an Altera FPGA, which the company sourced at a discounted price.

The Xilinx Spartan6-150-based mining boards achieved about 200 to 220 MH/s per FPGA, and sold for approximately $1 to $2.50 per MH/s.

Meanwhile, Butterfly Labs offered its dual-FPGA 830 MH/s Single for the very aggressive price of $600 (less than 75 cents per MH/s).

In mid-2012, BFL started to ship the so-called miniRig, a 25.2 GH/s mining device consisting of a PC tower-like case with nine intake fans on the left side of the chassis and nine exhaust fans on the right side. It contains as many FPGA boards as necessary to reach the nominal total hash rate of 25.2 GH/s. Typically, that's 17 or 18 boards with two FPGAs each. The Altera FPGAs on the miniRig’s boards are larger, more expensive chips than the ones on the Single’s board, operating between 650 and 750 MH/s each with significant variance.

Below: Half the boards of a FPGA-based miniRig, mining with cgminer.

ASIC-Based Mining Devices

Avalon

Avalon is the ASIC-based successor of Mr. Zhang’s FPGA-based Icarus device. The ASIC is a small, single-core, 110 nm chip. An Avalon rig consists of several hundred chips and achieves a hash rate of approximately 66 GH/s.

Butterfly Labs

Shortly after beginning to ship its FPGA miniRigs, Butterfly Labs announced the impending release of ASIC-based, 60 GH/s "SC Singles", as well as a 4.5 GH/s low-end product called "Jalapeno", and a 1,500 GH/s high-end product called the "SC miniRig". In order not to jeopardize ongoing sales of FPGA-based mining devices, BFL offered a trade-in-program where, upon the return of a BFL FPGA-based device, a customer would receive a full trade-in refund for a ASIC device purchase of twice the price, thus saving 50% of the ASIC-device’s purchase price.

Exactly 10 months after starting to take pre-orders for the ASIC-based machines, BFL commenced shipping the first device, a 5 GH/s device replacing the Jalapeno, but drawing about six times as much power. BFL admitted to missing the power specification of its 65 nm ASICs by an order of magnitude, essentially turning a would-be 8 GH/s ASIC (16 cores @ 500 MHz) into a 4 GH/s chip clocked at a mere 250 MHz.

ASICminer

ASICminer created a 130 nm ASIC for its mining pool, but have started to auction a few 10 GH/s boards and are in the process of commencing sales of a USB key-style 300 MH/s miner: the Block Erupter USB. While the auction of the former devolved into a bidding war that ended at the questionably-high price of 75 or 76 BTC per device, the USB keys are being offered at a fixed price of 1.99 BTC each.

Comparison of FPGA and ASIC Chips

Spartan6-150BFL SingleBFL miniRigAvalonBFLASICminer
TypeXilinx FPGAAltera FPGAFPGAASICASICASIC
Process45 nm45 nm (?)45 nm (?)110 nm65 nm130 nm
Hash Rate Per Chip210 MH/s415 MH/s650-750 MH/s280 MH/s4 GH/s300 MH/s
Power Draw15 W40 W35 W2.8 W30 W2.5 W
Efficiency (MH/s per W)141020100133120
US$ / MH/s1 to 2.50.750.6VariesVariesVaries
NotesTypically 1 to 4 FPGAs Per Board2 FPGAs Per Board2 FPGAs Per Board, 17 to 18 BoardsPriced In BTC (prices increase)BFL Anticipates A Slight Reduction In Power DrawPriced In BTC (prices increase)
  • Darkman69
    Finally a proper write up on Mining Bitcoin with the good the bad and the reality.
    Reply
  • esrever
    How does mining new coins make sense if there will ever only be 21 million? I am so confused by that point.
    Another thing is, with an economic system like this, a billionaire can easily manipulate market prices and make extremely large amount of money and still be completely fine due to this being in a grey area of the law. You can't pump and dump stocks legally but it seems pretty easy for something like this considering you can dump the bit coins off as currency in any country.
    Reply
  • s3anister
    10943052 said:
    How does mining new coins make sense if there will ever only be 21 million? I am so confused by that point.

    To quote the Bitcoin wiki page: "The last block that will generate coins will be block #6,929,999 which should be generated at or near the year 2140."

    So to directly answer your question, the whole reason for mining bitcoins is because you'll most definitely be dead before the last block chain is even completed.
    Reply
  • smeezekitty
    Shitcoins definitely = fools gold!
    Huge waste computing power IMO
    Reply
  • vmem
    10943126 said:
    Shitcoins definitely = fools gold!
    Huge waste computing power IMO

    someone needs to rewrite the algorithm and somehow hook up block generation to folding@home or some similar constructive use of the computational power.
    Reply
  • smeezekitty
    10943157 said:
    10943126 said:
    Shitcoins definitely = fools gold!
    Huge waste computing power IMO

    someone needs to rewrite the algorithm and somehow hook up block generation to folding@home or some similar constructive use of the computational power.
    That would be a great idea. Verifying a relatively small hash to screen out the cheaters then perform something useful like F@H.

    Reply
  • dannyboy3210
    A very interesting read. I had been reading about Bitcoins (mainly because I just couldn't figure out what they were exactly), but this clears a lot of things up.
    Also, at the bottom of page 5, in the Comparison of FPGA and ASIC Chips table it says "Power Fraw".
    Reply
  • slomo4sho
    Fiat currencies... I guess for some people the dollar wasn't worthless enough.
    It is amazing how you can lose your "wallet" and your funds permanently disappear from the pool.
    Reply
  • toarranre
    Never heard of this and I'm quite confused by it. Use graphics cards to find units of a currency that from what I can tell must be extremely succeptable to artificial inflation or all out collapse.
    Reply
  • phenomiix6
    www.bitcoinpaypal.info
    Reply