Does anybody have an experience with three GTX295 cards in one system ?

In general, two questions:

  1. Does it work (all 6 GPUs are detected and functional) ?
  2. How hot these cards will be under load when stacked without empty space between them ? The case is Antec P193 with two 120mm fans (front intake/rear exhaust), one 200mm fan (side intake) and two 140mm fans (top exhaust).

Thanks in advance.

  1. No known issues with XP or Linux. Vista, you’ll need to add registry keys.

  2. I don’t really know. Hot?

I have (kind of in pieces at the moment) a system that has four GTX 295s:

The short answers to your questions are:

  • Yes, I didn’t have any troubles with 64-bit Linux (RHEL5).
  • In the custom case (with 3x 120 mm fans blowing on the ends of the cards), the backplate got pretty hot at full load. It wasn’t quite at burn level, but was pretty uncomfortable.

I haven’t got temperature numbers for you because a different project required I gut the machine temporarily. (Apparently, I only get one computer that isn’t a useless cookie-cutter Dell, and needed to solve a problem.)

i would look into watercooling. the single PCB cards run cooler, the dual PCB cards are very hot.

i would also suggest waiting for the gtx 3xx cards, i would guess they will be out in a month. total guess, but i know it will be soon

Watercooling is by far too much… :) I’ve had 4 GTX295 in one system and it operated fine with fans only.

I’d recommend on only 3 GTX295 though, I think the forth is too much…


Do you remember precise temperature numbers for such a setup (4xGTX295) ? Thank you.

I think you’ll be interested in the FASTRA II project ( They put 6 GTX295 and a GTX275 in one case. With the side of the case open and normal air cooling only, the maximum temperature they measured was about 60 degrees celsius.

They did need a custom BIOS from ASUS ( But, from what I read there, you probably won’t need it for three cards only.

Thank you for the link, very useful!

Thank you for the info … Why did you decide to use Manifold Custom Revision 2 case instead of something more traditional ?

Curiosity and space. Most of the cases which can accept 4xGTX 295 cards are enormously overbuilt if you just want a GPU compute node, and not 12 hard drives, 4 optical drives, etc, etc. This is a very nice compact box that I can slide into the bottom of our rather full rack. I also have need from time to time to make custom enclosures (not for computers), so this seemed like a good way to check out the build quality of Protocase.

This is the AMD machine I used for 4 GTX295, altough I think 4 was a bit too much for it :)

with 3 it worked fine…

1 Termaltek VH6000SWA Chassie

2 Power Supply 1500W

3 Foxconn Destroyer nForce 780a

4 AMD Phenom 9850 2.5 GHz quad-core

5 8GB(4x2GB) DDR2DIMMs fromKingston DDR2 800

2 WD SATA 500GB 7200 rpm 16MB RAID 24/7 5YR WARRANTY


I’m planning to build a 4xFermi box when the cards are out (I’ve built three 2xGTX295 boxes already, now it’s time to scale up).
The case is actually the hardest decision. I think I am going to use the new Raven 2 case. It’s got the required 8 backplate slots (hard to find even in large cases!)

It’s also unique in boosting GFX airflow by rotating the motherboard so the air flows from bottom to top. Three huge (180mm!!!) fans blow right at the cards. I think this is going to give much better air cooling for 4x graphics boards.

Motherboard is a no-brainer, the Asus P6T supercomputer is a solid workhorse.

It is great to know the config, however, I’ve asked about the temperature :-) May be you remember exact temperatures those four GTX295 cards were working under ? Thanks in advance.

Great case! Thank you for the link …

Your initial Antec p193 also looks good for 3 cards… it has a SIDE fan which may help cool the cards. it can hold 3 cards but not 4 (only 7 slots).

I’ve built my 2x 295 boxes using the Antec p180 and 2 p183s with no problems.

I found a picture of the Raven 2 showing 4 full size cards… (these are GTX295s and for some reason a Radeon in there too…).

Note the GIANT fans at the bottom and the unique vertical motherboard.

This image also shows a water-cooling radiator (blocking much of the fans) but I plan to run air-only.

Great case and very informative picture … definitely, I will memorize this hardware for future assemblies.