1500watt PSU

this case holds two http://www.newegg.com/Product/Prod [...] bPC-A7110B

actually there is a spot on top and one on the bottom

The antec p190 has a spot for two on the bottom but unfortunately it allready comes with two power supply's that aren't that great

http://www.antec.com/us/productDet [...] odID=81900

http://www.performance-pcs.com/cat [...] s_id=21710

Hows about:
http://www.performance-pcs.com/cat [...] s_id=22094


The Ultra X3 1600W has: 4x PCIe 6-pin & 2x PCIe 8-pin. So all you need is 2x PCIe 6-pin. All you need is to cannibalize 4x molex connectors to make the additional 2x PCIe 6-pin you will need. It has a single 12V rail so that should not be an issue.


Bob

if you need a case for 4 9800gx2 (can you even do that, im not sure, i was under infulence it was capped at 3 by motherboard constraints.) the only case i would consider would be the coolermaster stacker it is a beast of a case. and with a billion 120mm (5" ) fans cooling thos card wont be to much of an issue. at least check it out.

i can help but think that actually 2 lots (or three) of the GTX280 will have a higher performance yeild than the 9800's you specified.

p.s. most powerplant in the usa are on COAL burner. eew so much co2

Thanks for all the replies.
You have to remember, 1500watt is the output, and is only about 80% of the total power consumption of the device. Total power consumption is about 1875 watts at full load, and a 15 amp circuit only supplies 1650.

Nvidia is a must for this because of CUDA.

There is only one motherboard that has the slots setup correctly for 4 double thickness cards, and i've talked to the company and they say that there is no inherent constraint on 4 cards. SLI will not work for 4 cards, but SLI is irrelevant to my uses.

The problem with all the cases mentioned so far is that they only have 7 expansion slots. Since I have 4 double thickness cards, I need at least 8. The one in my original post has 10. I'm curious if anyone thinks that I could fit another psu at the bottom of the case, or if they can find another case with 10 expansion slots.

@BobWy: Thanks for pointing out that PSU, it looks like a real potential. I assume you mean 8 pin. A quick search brings up a number of cheap molex to 8 pin connectors, so that will work great. Looks like the best option so far.

Any other PSUs?

EDIT: http://www.newegg.com/Product/Prod [...] 6811133053 the Xaser VI case by thermaltake also has 10 expansion slots. Do you think it will be better than the Lian Li I mentioned at the top? I'm inclined to think not. The Lian Li has an ungodly number of fans, and cooling is going to be critical for this. I'm inclined to water cool the CPU, mostly to get as much heat away from the cards as possible. Do you think thats a good idea?

Well, if you missed it (you might) there is the FASTRA computer. A tomography computer with a very similar setup to yours. A brutal crunching machine like yours.

Here your are:
http://fastra.ua.ac.be/en/index.html

Have fun !!

Yea I'm following generally what was done with FASTRA. I've looked into water cooling, but for now it doesn't look like funds will support that.
Each block runs ~$180 plus all the radiators.I ought to be able to expand to water cooling later on, there is no imperative to do so now. The good news is the computer will be kept in a separate air conditioned container, which will allow the cards to be overclocked some.

That said, I'll need to look into the performance per dollar ratio of water cooling the setup vs. building another box and using MPI for courser grained parallelization, and then CUDA for everything else. Looks like I'll go with the Lian Li I first mentioned, its the best case with 10 expansion slots.

There are still some details to be sorted out with the corporate sponsors (I'm not doing this on my own dime...) so it may be a few weeks before its up and running. I'll post pics when I do though.

EDIT: If I were to water cool the cards which radiator should I use. I expect that I would have two seperate water cooling systems, with two cards on each. Each card produces ~200watts of heat.

Thanks, thats extremely helpful.