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25

EDIT: My original answer may have made sense back when the question was asked, but now it is clear that Butterfly Labs cannot be trusted. As they say, "fool me once, shame on you; fool me twice, shame on me". After all the delays and controversies with their FPGA line, they have given their word that with the experience gained they really will be able to ...


21

First a bit of perspective on FPGA mining. ​ Around 2011 some miners started switching from GPUs to FPGAs, (Field Programmable Gate Arrays), after the first implementation of Bitcoin mining came out in Verilog, (a hardware design language that’s used to program FPGAs). The general rationale behind FPGAs is to try to get as close as possible to the ...


20

I co-founded LargeCoin, Inc., and we really are developing an ASIC for Bitcoin mining. As earlier replies pointed out, the unit cost of ASICs is far lower than FPGAs once you get beyond a few hundred units. The up-front cost of ASIC production varies widely depending on the process you use. On the cheap side, there is so-called "wafer sharing," where your ...


18

An FPGA is cheap in quantity one ($100-$300) but expensive in quantity 1,000 ($50,000-$3,000,000). They can mine decently (200MHash/s or so), but are not cost effective yet. (They do, however, consume much less power than GPUs.) An ASIC is expensive in quantity one ($2,000,000) but cheap in quantity 100,000 ($5,000,000). They can mine unbelievably well (...


13

The BFL single produces high stale rates on P2Pool because of the way its firmware is designed. The BFL does 2^32 hashes and then reports any shares found. This takes it about 5 seconds. With solo mining or typical pools, the work unit you get is valid for several minutes or until a new block is found (on average, one every ten minutes). So the average ...


11

The very basic idea of an FPGA is that it can be loaded with a specific firmware (a layout of logical gates, in essence). That page contains the firmware you'd need to load onto a Xilinx FPGA (A Spartan 6) in order to use it as a mining device. ZTEX refers to a suite of the FPGA, and various IO controllers (USB, etc.). Roughly speaking, the steps you'd need ...


10

You would need a computer to program the FPGA, obtain the work units, distribute them to the FPGAs, collect the shares, and submit them back. If you're not using a mining pool, you'll also need the computer to generate the work unit, assemble solved blocks, and submit them to the Bitcoin network. The computer won't be doing that much work. So you can use a ...


9

Beyond the concerns about BL's ability to deliver, should they be successful it's very questionable what kind of return you'll be able to get as an individual user even with the substantial increases in efficiency they promise. With Bitcoin mining, the number of coins dispensed in a given time period is fixed and self adjusting to the relative strength ...


8

So is there a nice tutorial which explains how to start mining using FPGA. Not really, not a "starting from scratch" one. Or this is so complicated? Yes, it is quite complicated - in order to work with FPGAs, some additional skills on top of software are required. You need to understand logic design and some (fairly basic) electronics in order to make ...


6

Yes, there are designs for Litecoin mining FPGA bitstreams, but they are not very efficient currently. ASICs are much more efficient and if anyone finds it lucrative to invest in development of Litecoin mining ASICs, they will push out GPU mining. (The efficiency ratio between ASIC and GPU will be lower than with Bitcoin though).


5

I have sent Butterfly several emails inquiring about delivery dates, and etc after pre-ordering the Jalapeno. I have yet to get a response back now 4 weeks later, I have sent them another request...this time asking for a refund. I think they should of put a lot more info out there about how long it would take to get our orders. I don't want my Miner next ...


5

The statement "treat it as an FPGA" doesn't make sense. Both RAM and FPGA (or ASIC) are electronics but that's where the comparison ends. RAM is designed for one specific task and cannot by itself do calculations required for mining.


4

It uses ~70W @ 12V of external power. The stock power brick is cheaply made, giant, and inefficient (PF=.5,efficiency~.8). Fortunately, the power brick can run on 240V. Many people make their own cables to use an ATX or bench PSU (with higher powerfactor and efficiency) source: https://bitcointalk.org/index.php?topic=67819.msg796852#msg796852


4

I preordered 3 jalapenos. I made a calculation about the net profit with them. If right now a ATI card of about 150 USD gives about 350MH/s and produces about 0.125 BTC/day, a new Jalapeno costs is 150 USD with 3.5GH/s, so it should produce about 1.25BTC/day, and be like having 10x ATI cards. Maybe it will deliver a little less, because the cost of energy ...


4

According to Butterfly Labs' customer service department, their chief operating officer, and their vice president of product development, the speeds they claim for their BitForce products are all nominal speeds and a variance of +/-10% is permitted. As of this writing, they say speed claims are based on a combination of synthetic benchmarks and averaged real-...


4

Litecoin uses scrypt instead of sha as its crypto function. Scrypt is a memory hungry algo, so it's very difficult to have efficent implementation on ASIC or FPGA at current technology. This choice was made to prevent ASIC and FPGA specialized mining in favour of more diffuse and generalized mining with standard hardware. UPDATE After just about 3 months my ...


3

Any MH/s rating on any device should be considered an estimate. Actual capabilities will vary on a device-by-device basis and external factors such as ambient temperature and network connection speed/stability also enter into the equation. You will also notice a difference between the hashrate as measured by your mining software and the hashrate as reported ...


3

Currently the hash rate is around 25 TH/sec. It is expected that when the ASIC hit the market in Dec 2012, the new hash rate will be about 250 TH/sec. The difficulty is directly proportional to the hash rate, so it should also increase 10x. This would reduce the profitability of existing GPU miners by 10x. Plus about the same time the block reward will ...


3

See: Open Source FPGA miner and additional info


3

From what I know, you can connect basically any amount of FPGA cards to one computer through USB hubs. Case in point:


3

Bitcoin mining is essentially just the repeated calculation of sha256 checksums. Given that sha256 is a fairly simple algorithm that uses only basic integer calculations absolutely any processor core should be capable of churning out sha256 checksums very quickly and any added complexity beyond the basic instructions required for sha256 is wasted. To that ...


3

I'm a total newbie but so far the problem appears to be solvable. This is what I did with my Altera DE2-115 hooked-up to a Windows 7 machine: got fpgaminer's open source FPGA bitcoin miner on Github got mining proxy on bitcoin.cz set up an account with slushpool.com (had to use VPN because my ISP apparently blocks connections to slushpool over http :((( ) ...


2

FPGAs and GPUs are reprogrammable, so you can use them for anything. FPGAs require some specialised programming, while GPUs just use OpenCL. ASICs have specialised chips highly optimised for mining and only mining. I don't think they could ever be reprogrammed or reused to do anything else than mining blocks according to Bitcoin rules. As for what to do ...


2

Playing by the rules, doing the right thing is of the utmost importance. This often times causes situations that are much harder to deal with or endure, as well more expensive. Understanding that when we buy from a company we advocate for them, through the purchase from them, we as consumers empower them to grow and proceed. It is critical that we ensure the ...


2

It has now been confirmed by ngzhang that BFL is using Altera Stratix III EP3SL150 FPGAs in their singles. Since Altera has made product reliability data available, we now at least have the appropriate info available for the chips themselves. The EP3SL150 testing gives it a FIT rating of 15.1 which corresponds to roughly one failure per 66,226,166 hours or ~...


2

That's about all there is to it. You don't need to handle the Bitcoin protocol or worry about the blockchain, the mining pool does all that for you. Just issue a request for 'work' to the pool using the JSON-RPC interface. Hash the supplied work with different nonces over and over until you get a hash less than the given target, and use the JSON-RPC ...


2

It depends on the board. There is a board that uses USB for its connection to the computer.


2

You could possibly buy some FPGA miners. The ASICs can only do Bitcoin's specific hash function, and won't be of any use for your research.


2

The data that is being hashed is constantly being updated. The block header contains a time field and updated every few seconds. If it doesn't timeout and reset (get new work) the algorithm will be working on a stale header. "When generating, you constantly hash the block header. The block is also occasionally updated as you are working on it" https://en....


2

An FPGA can do anything, by definition (Field Programmable Gate Array) they can run any bitstream you care to write for a specific task. The BIP0032 wallets you're thinking of however are 128bit keys with significant key stretching, so not a chance in hell will you ever crack one. That's by design.


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