Yes. However, the main purposes here is to minimize all costs where possible. Also, if I really want to optimize, I need to be exposed to as much of the FPGA circuitry as possible.

About the miniature board that has the pads that he soldered the FPGA chip to. It has pins on the outer edge to plug the mini-FPGA board to the slightly larger board. Do you think the solder balls are all accounted for by a pin? (i.e. one for one.)
Is that mating pair a product of Xylinx? Can those boards be made using a regular DIY etching process? If it requires multiple layers, then I don't see how it could be practically done....but to be thorough, I prefer to ask anyway.

Thank you for your response. I can see how that would be impossible by hand.

What does the chip mount to exactly? I like how in RPH's thread [see below] he has his chip mounted to a tiny board which then mounts to a larger board. This seems like a good approach in the event an FPGA needs to be replaced.

One of the reasons I see this whole thing as a possible for DIY, is just reading RPH's thread where he used a skillet or something. See here: https://bitcointalk.org/index.php?topic=44891.0
If he can do it, why not anyone? Despite the chances of losing a chip here or there, I think such a process could be fine tuned to be overall successful & repeatable.

What he has there in that thread is [seems] very elegant and simple. Though, I am uncertain about what happens under the FPGA... Is a multilayer PCB required for our purposes? (i.e. btc mining)

||bit.out

Nice work. I'm interested in this. Seems quite concise.

Would you/they sell these in kits for DIY assembly? Or the schematics and software? From reading other threads, I see there is a lot of interest from people wanting a DIY format to save more money (if possible), or pehaps to just get their hands more involved in their bitcoin mining.

Congrats to whoever is behind it.

||bit.out

Thanks none-the-less for your thoughts.

Where do you find a proposed 4xLX150 option? I found one posting, but it seems to be a time limited offering proposed. I think selling at manufacturing cost for a short term.

I'm not fully aware of the requirements to mount an FPGA chip. Just that it has a lot of pins to solder to the board. Could you explain in layman terms what you mean when you say "but even with a reflow oven doing the BGA FPGA would be difficult without a stencil"?

||bit.out

Good CSI work to relate the two. It makes sense now.

It also makes me wonder how much this apparent affinity or aptitude towards mathematics has anything to do with how well their product efficiently hashes compared to others FPGA approaches.

Was this essentially a kit one could use to make an FPGA miner board? Do you have any links?

If it is a kit, then it seems this would yield at least a very competitive MH/$ option (assuming 150MH/s per board) compared to other retail boards (excluding BFL).

||bit.out

Thanks for the link BinaryMage.

From my limited knowledge on this topic, I expect the hardest part to be getting the prices down. Granted, part of that would be in optimizing FPGA code. But getting the code initially may be as easy as using what has already been developed for open use (if any). There is an open Python code I think that you can analyze to see how the algorithm is used. But I would personally start with some block diagram level stuff first. I've yet to find any such diagrams though.

My thinking is that any low cost DIY will [probably] incorporate Spartan 6s150 chips. However, I don't want to be tunnel visioned and/or dogmatic about that idea. Also, I'd like to take time to think outside the chip    It may be that the best low cost solution would require buying more parts than a minimalist board. Perhaps, any ASICS to do the SHA256 hashing? Maybe, use the FPGA's to do whatever else needs to be done.

Brainstorm:
From some cursory reading, I would expect any dedicated SHA256 ASICs to do the hashing part of the overall algorithm about 3 to 4 times faster than an FPGA (i.e. pound for pound). If a such a dedicated ASIC could be used for this, then for each hashing routine the ASIC would perform, let's say we can free up say three hashing routines from the FPGA. And I anticipate this to be a large part of the FPGA code. Anyway, the FPGA would use any such free space to process output from (or for) the ASIC as needed.
From there, figure out the right ratio of FPGA's to ASIC's to utilize every ounce of logic circuitry. This MIGHT work to increase MH/$ (MH => MH/s) if the ASIC work:cost alone would translate into a higher MH/$ value.

Another thought might be to consider how a GPU can work with FPGA's.

...

Back to 'normal' thinking:
Anyone got any idea on what a minimalist board might cost? Assume the FPGA can be programmed to achieve about 150Mh/s. Already we are at a disadvantage in MH/$. Such a chip might cost about $170 (not sure if that is accurate). Anyway, if that is the case, you start out with 150MH/s/$170 or  .88MH/s ... not counting the printed circuit board and any minor components (capacitors, resistors, connectors).  Just from that alone, I would decide to go with whoever is the bext retail FPGA. But I wouldn't want to give up so easily.


||bit.out

Thanks for your thoughts.

For DIY, what would you suggest to accommodate this problem? A premounted FPGA chip on a daughter board? Akin to one RPH seemed to use here: https://bitcointalk.org/index.php?topic=44891.0

BTW: RPH seemed to pull off something like that at his home: https://bitcointalk.org/index.php?topic=44891.msg536983#msg536983

Thoughts?

And it must be low cost, i.e. it must be competitive with two of the top three FPGA boards in MHash/$.
Otherwise, it's just fiscal sense to just do the retail option. BFL, ZTEX, et. al.

I think DIY would have the advantage, since you automatically cut out the profit aspect. However, there are some disadvantages of DIY  -- e.g. individuals have a higher hurdle to receive any bulk discounts (which might be able to be met by pooling DIY'ers purchases), or any special or costly equipment needs.

That sounds good too. Though, I'm even curious about the potential for a DIY PCB. What necessary PCB complexity is there to accommodate to an FPGA chip. One thread I read seemed to indicate a 4 layer PCB would be a minimum. If-so, then yeah, I don't see that happening easily in a DIY venue. Which would mean having the PCB made professionally. But that may be the one thing that needs to be bought in bulk. And if it is as simple as RPH's boards seem, then it shouldn't be that costly at all.

BTW: I am pretty sure RPH soldered his own FPGA to a BGA board. That was part of his excitement in using a skillet or hot-plate to do so. It appears this is the BGA board he used:
http://www.xilinx.com/support/documentation/package_specs/fg484.pdf

So, a professional outside PCB source seems to have been his approach as well. There may not be any practical alternative for DIY.


||bit.out

 

I'm glad to see some initial interest in this. Though, it isn't much of a surprise having seen the other DIY FPGA threads.

I'd personally like to bypass all the fun of designing one, and use someone else's already made DIY plans. My expertise is as an electronics technician, not an engineer. In the meantime, I might go with Butterfly Labs products.

....

There are good ideas already posted and well commented, but nothing finalized. I personally like the thread started by RPH here: https://bitcointalk.org/index.php?topic=44891.0

RPH's o/p reads "Ultra-Low-Cost DIY FPGA Miner - 175MH/s @ $1/MH". i.e. 1MH/$

If his design path actually would yield 1MH/$, then that DIY approach seems quite worthwhile...b/c BFL Singles is the best at about 1.38MHash/$. The next best two found here (https://en.bitcoin.it/wiki/Mining_hardware_comparison#FPGA_Devices) are 0.82-0.5 MH/$ made by ZTEX (but the best rate there requires a bulk purchase), and the very comparable 'X6500 Rev 3' at .71MH/$.

So, 1MH/$ seems very nice for DIY...even considering some of the new stuff that seems ready to come out. Furthermore, the MHash/$ might possibly be improved more with some creative thought.


Any thoughts?

Maybe go to this thread for some other insights to consider:

"Minimalist Spartan6-LX150 board"
https://bitcointalk.org/index.php?topic=45532.msg543312#msg543312

...

I'll see what kind of responses we get, and if anyone wants to contribute, I can certainly think of plenty of questions to ask.

||bit out.

Does anyone here understand what is delivered by Amtel with this service or product? An FPGA chip or a kind of hybrid?

http://www.atmel.com/products/Other/fpga_conversion_ulc/default.aspx

Moved to:

https://bitcointalk.org/index.php?topic=78935.0

Using retail or bulk-purchased components: Has anyone here developed any actual low cost do-it-yourself FPGA boards that have competitive or better-than competitive hash/$ rates?
If-so: Is that person willing to share or sell the design plan?

I've seen a few threads attempt to tackle this topic, but I have yet to see anything actually come from them. It seems the thread authors drop out or decide to develop the idea for their own use after some progress.

If not: Is anyone here willing to collaborate on developing such a board? And not just an FPGA board that will hash, it MUST be competitive in price...if this is even possible. It seems, so far, the best hash/$ rate is BFL's products. But if a board could be developed to be at least as good as the next best hash/$ rates, it might be worth it. Especially considering the slow product shipping time of Butterfly Labs.

Using retail or bulk-purchased components: Has anyone here developed any actual low cost do-it-yourself FPGA boards that have competitive or better-than competitive hash/$ rates?
If-so: Is that person willing to share or sell the design plan?

I've seen a few threads attempt to tackle this topic, but I have yet to see anything actually come from them. It seems the thread authors drop out or decide to develop the idea for their own use after some progress.

If not: Is anyone here willing to collaborate on developing such a board? And not just an FPGA board that will hash, it MUST be competitive in price...if this is even possible. It seems, so far, the best hash/$ rate is BFL's products. But if a board could be developed to be at least as good as the next best hash/$ rates, it might be worth it. Especially considering the slow product shipping time of Butterfly Labs.

The card's actual value isn't based entirely on how cost efficient it is at mining bitcoins. Though, admittedly those interested in this forum may see it that way.

It's not the most cost efficient card, but it is the most compact GPU for mining. This means (I think so far) that the advantaged cost per megahash for the cheaper cards would be slightly diluted (i.e. from a caluclation as you showed), when you consider the cost of needed hardware to support the cards (e.g. chassis, cpu, mobo...etc..). For example, considering only the card, you might have a cost ratio of 2:1 (where 1 is half of 2), but if you add 0.5 to each side (simulating cost of equal supporting hardware)... the ratio is 2.5:1.5 where 1.5 is more than half of 2.5 - perhaps trivial, but noticeable.

Regardless, considering your points again for this forum, I may reconsider the GPU fraction of the cost...but probably wouldn't sell them below retail.

Also, I will reconsider the requirement of the chassis. They can probably be relatively easily sold seperately on Craigs list.

There are nine other chassis (each with CD drive and floppy drive) needed to be include in that calculation.
However, I'm not counting the CD drive or floppy drive in the value. It's part of the chassis from my view. And the SSD drive is maybe $100 (not $300)...so subtract $230.
But still add the nine additional chassis.

Keep in mind, the 6990's are high demand/low supply. They are the highest performance GPU's for mining, and are hard to find avaialble for any timely delivery. As proof, try to find a 6990 that is immediately available online. I haven't checked in a while, but I'd bet you'll find them either sold out, not in stock or weeks from delivery. From just that, they carry more value than retail costs.

As for condition, the system has been used for only a month now. Proven to work. The extra chassis are in excellent condition.

Just trying to get rid of everything. Also, I want to see if the interest is there.

I'm debating to sell my rig and extra chassis. This is just a guage for interest....

1 newly built, working mining Rig. The SSD drive would be wiped before any sell.
...Motherboard, MSI 890FXA-GD70
...1200W power supply (good quality)
...SSD Drive
...AMD Anthlon 2
...2G RAM..might be 4G.
...Quantity of 2, Radeon 6990's. (hard to find available anywhere online)
...optical & floppy drive
....4U rack mountable chassis

Also, purchase must include the 9 other 4U rack mountable chassis (almost new condition). No special name brand... they are empty other than that I am pretty sure they all have one optical drive and one floppy drive in each.
One could build a the foundations for a pretty sophisticated mining operation with these 10 chassis.

--------------------------

The chassis LOOK kind of like this...but just generally: http://www.newegg.com/Product/Product.aspx?Item=N82E16811128064

Conditions:
Buy everything in 'as is' condition....cash only and pick up only (location Temecula, which is north of San Diego on interstate 15).

I'm looking for $3000 for the whole lot.

If I can't sell it all, it will just keep mining.

Post replies about your level of interest (if any) or send me an email (see profile).