Custom FPGA Board for Sale!

[Keninishna]

all you really need are usb ports so I imagine a lot.

[fizzisist]

6.8W isn't a lot compared to a GPU but it is a TON compared to these FPGAs that normally run at 3 watts or below. FPGAs are really being pushed in these applications.

Does that affect the expected lifetime of these?
What's the expected lifetime at the normal 3W?
and the expected change to that at 6.8W?

Mining is 24/7 - so those lifetime expectations would be rather critical.

Xilinx publishes some reports on reliability tests: http://www.xilinx.com/support/documentation/user_guides/ug116.pdf

I haven't read through that all yet, but the interesting test is probably the High Temperature Operating Life Test. It looks like they tested the Spartan 6 (XC6Sxxx) at Tj > 125F for 533,351 hours. They somehow scaled it to "equivalent hours at 125F" to 1,161,865 hours. That's 132 years. Not sure how to interpret the fail rate, but it's either 0 or 10%... Either way, I don't think failure is going to be a problem, but please use some type of heat sink. The better that you cool the FPGA, the less power it will consume, just like with GPUs or any semiconductor. We plan to ship the boards without heat sinks, so that you can put on whatever you like. We'll offer a suggested one, that should work well enough without a fan. Increasing airflow with a simple fan never hurts, though.

If I want to give this a try, what's the most barebone computer I can use? Let's say I want to build a dedicated FPGA miner. I can get a cheap motherboard since I don't need PCIe slots. I can go with a small PSU and if I do LinuxCoin on a USB stick, I don't even need a hard drive. If I want to go all out, how many of these can I put on a single motherboard?

The USB bus allows for up to a maximum of 127 devices, so you should just need a bunch of hubs to get pretty much as many as you like. There might be some other issues with running multiple boards, though, because it's never been tested yet, but that should all be worked out in software. The smart thing to do would be to wait until someone confirms that they got multiple running before you place an order for 127 of them

[newMeat1]

kano- that was a tough question     You made me do some serious googling. Here's a paper about how Altera tests their FPGAs. Altera is the other major FPGA maker besides Xilinx.
http://www.altera.com/literature/rr/rr.pdf?GSA_pos=1&WT.oss_r=1&WT.oss=Altera

They test by doing voltage cycles, temperature cycles, humidity cycles, configuration cycles... you get the idea. The good data starts on pg 12. It looks like all of their devices should last at least 10 million hours!

EDIT- fizzisist beat me to it by a couple minutes! Well, now you have 2 independent sources for your reading pleasure

[kano]

Thanks - I guess I could have done it myself in hindsight, but I thought you guys would already know
Well certainly suggests they should last more than at least a few years even with adverse usage.

[ElectricMucus]

They test by doing voltage cycles, temperature cycles, humidity cycles, configuration cycles... you get the idea. The good data starts on pg 12. It looks like all of their devices should last at least 10 million hours!

That's 1141 Years...

I doubt this figure is somewhere in the datasheet.

A common mtbf for ics is usally between 100000 to 500000 hours which is still enough.
mtbf means mean time between failures which is the time by which 50% of the devices have failed.

Although failure rate follows the bathtub curve which means some ics fail very early after which almost no failures occur over a long period of time after which it exponentially increases.  Modern ics and especially high revenue items like fpgas are extensively tested so that almost any initial failures are sorted out.

The important part though is that the mtbf is only viable for running the chip within specifications, if that is the case here only the developers can answer... hint, hint

[molecular]

UPDATE0 Aug 19th 10:00 - I ordered Xilinx USB platform cable through ebay.de for €41.50 = $59 incl. shipping from HongKong.

UPDATE1 Aug 19th 10:10 - I received an invoice from Li via paypal and payed $440 (+$12 for shipping and handling) = $452. I noticed my shipping address in paypal was a very old address of mine and PMed Li with the correct address. I hope it'll work out.

UPDATE2 Aug 19th 10:20 - Li confirmed receiving the payment and also confirmed he would send to the correct shipping address.

UPDATE3 Aug 23rd 06:42 - PM from Li, saying he shipped the board! Gave me tracking-# and ETA 6-8 days.

[jav]

Another question: Could this be cooled by submerging it into a small aquarium filled with mineral oil? Would one still use a heatsink in such a situation or is that unnecessary, with a liquid cooling solution?

[tnkflx]

Are all pre-orders sold out?

[li_gangyi]

Another question: Could this be cooled by submerging it into a small aquarium filled with mineral oil? Would one still use a heatsink in such a situation or is that unnecessary, with a liquid cooling solution?

Jav: It could be, but it's seriously overkill for this. I'm sure it'l be seriously messy though.

[li_gangyi]

Are all pre-orders sold out?

The initial 4 boards are sold out, I do have the 1st board that I assembled. I can sell that @ the same price if you're interested, let me know.

[Philj]

I'm interested in ordering one of the Gen2 boards. Is there any consideration for adding a mounting bracket to them so they can be mounted in a case like a PCI card (just not plugged into the motherboard)?

[newMeat1]

The important part though is that the mtbf is only viable for running the chip within specifications, if that is the case here only the developers can answer... hint, hint

It is within specs. We definitely aren't overvoltaging or overclocking them

Are all pre-orders sold out?

No- Cablesaurus hasn't started taking preorders yet. Look for a post on here when he starts taking them.

Could this be cooled by submerging it into a small aquarium filled with mineral oil? Would one still use a heatsink in such a situation or is that unnecessary, with a liquid cooling solution?

I like the mineral oil idea, too! I had a post about this earlier-- you wouldn't even need an aquarium, just a tin box or something that is about 5in x 4in x 2in. I'm sure you wouldn't need a heatsink, because there would be mineral oil both above and beneath the chip. Also because of the convection of the oil. From what I've heard, mineral oil conducts heat 10X better than air.

From a practical standpoint- if you put a big-ass heatsink on each chip, then passive air cooling will be just fine. We're still talking about it, but that's probably what we'll end up doing.

Is there any consideration for adding a mounting bracket to them so they can be mounted in a case like a PCI card (just not plugged into the motherboard)?

Our only mounting consideration is some holes for standoffs (aka spacers), which would allow you to stack boards vertically. My best idea, for putting one inside the case, would be to put some zip ties through these holes. I'm sure you could find some wires or something to zip tie it to.

[teknohog]

Another question: Could this be cooled by submerging it into a small aquarium filled with mineral oil? Would one still use a heatsink in such a situation or is that unnecessary, with a liquid cooling solution?

Why would you want to do this?

I wouldn't want the small, whiny fan of this design anywhere near my apartment, but there are lots of better cooling solutions, and you can often go passive with a little thought. These typical designs where a fan is trying to push air through the chip, are clearly results of absolutely no thought to fluid dynamics. They are sometimes better off without the fan, especially if there is some airflow in the case already.

There are over 100-watt GPUs with fanless air cooling. I have one of these (a HD5770), also most of my CPUs have fanless heatsinks. My FPGA board is also doing fine with a passive heatsink.

[Christian Pezza]

as support of the project I would like to pre-order one as soon you guys are ready

ps
I understand the cost it's very high but if you just considering how much $/Watt u saving in the long run just right here u making the payback especially if u get a quantity, where the compounding get quicker. I am considering only one right now just because I like to get familiar with the system where I understand the writing but I am not familiar with the practice.

I am trusting the project as well I am trusting the Bitcoin community where I have already spend a lot of my time and money not for greed but for a developing of a better system and community.

[fizzisist]

I wouldn't want the small, whiny fan of this design anywhere near my apartment, but there are lots of better cooling solutions, and you can often go passive with a little thought. These typical designs where a fan is trying to push air through the chip, are clearly results of absolutely no thought to fluid dynamics. They are sometimes better off without the fan, especially if there is some airflow in the case already.

There are over 100-watt GPUs with fanless air cooling. I have one of these (a HD5770), also most of my CPUs have fanless heatsinks. My FPGA board is also doing fine with a passive heatsink.

The next board is planned to have a passive heat sink only, and we will most likely sell some boards with no heat sink so that you can use one of your own choosing. I believe the previous heatsink/fan combo was used just because Li had those sitting around already, and it works.

[jav]

Another question: Could this be cooled by submerging it into a small aquarium filled with mineral oil? Would one still use a heatsink in such a situation or is that unnecessary, with a liquid cooling solution?

Why would you want to do this?

I could better justify the price tag to myself, if I can build something interesting to put into my living room or somewhere. For that I want it to be silent and "hey, have a look at my money-making aquarium" seems like a nice conversation starter. :-) From reading the beginning of the thread, I got the impression that quite a bit of cooling would be necessary, so that's why I liked newMeat1's mineral oil idea.

But of course, if passive cooling is possible and safe, I'm all for it! So will this second generation of boards already be cooled passively? If that is the case I'm probably interested in a pre-order.

[mikegogulski]

Hi folks,

I saw up top there was an issue with lack of escrow, but that it got sorted.

I'm willing to provide a manual escrow service, through the end of September, for this project's sales only. Zero fees.

[flyswatta]

If I want to give this a try, what's the most barebone computer I can use? Let's say I want to build a dedicated FPGA miner. I can get a cheap motherboard since I don't need PCIe slots. I can go with a small PSU and if I do LinuxCoin on a USB stick, I don't even need a hard drive. If I want to go all out, how many of these can I put on a single motherboard?

When will this be available for pre-order?

Most barebone? SheevaPlug - $100 and done.

http://www.slashgear.com/marvell-sheevaplug-99-linux-pc-hidden-in-a-wall-wart-2435556/

Apparently there's a whole community regarding these things - complete with servers, etc.  http://www.plugcomputer.org/

I can imagine a power strip with these things hanging off of it with usb hubs hanging off of them with stacks of fpga cards.

[teknohog]

Most barebone? SheevaPlug - $100 and done.

Good luck running the requisite Xilinx software on ARM. Even if you can program the FPGA (using something open like UrJTAG), further communication for actual mining might turn out difficult. This is one reason why I implemented serial port communications in my version of the FPGA miner.

[ElectricMucus]

Most barebone? SheevaPlug - $100 and done.

Good luck running the requisite Xilinx software on ARM. Even if you can program the FPGA (using something open like UrJTAG), further communication for actual mining might turn out difficult. This is one reason why I implemented serial port communications in my version of the FPGA miner.

lolwut.

They plan on using a legitimate usb interface for the next gen chips as for the xilinix software, that it entirely independent once programmed a fpga can be anything, this is kind of the point of fpgas.