View Full Version : Ultimate GPU Folding Machine
=[PULSAR]=
03-16-2010, 11:20 PM
Saw this over on another forum he used 12" pci-e risers. What do you guys think. Was thinking about fully populating a 7 slot board with 9800GX2's or GTX295's I wonder what kind of PSU you would need to feed that thing.
http://img7.imageshack.us/img7/7797/gpufarming.jpg
INFRNL
03-17-2010, 12:23 AM
You will have to do your homework. If I recall I thought I saw another article about something similar and they had to have a custom bios made to run all the cards, but otherwise would be sweet
[XC] Oj101
03-17-2010, 01:13 AM
Regarding the above, could anyone be a bit specific on the issue with the custom BIOS? I have a customer who is about to buy an Asus P6T7 to run 3x7 monitors.
=[PULSAR]=
03-17-2010, 01:16 AM
From everything that I have read manufacturer's bios' are not made to read more than 8 gpus. Hence the custom bios to read more than that. Your customer should be okay.
p2501
03-17-2010, 05:02 AM
Saw this thread and I must admit the solution in the first post is quite nice (and practical - I guess it's easy to keep cool that way).
Concerning maximum GPUs in one system, the limitation seems to be 13, 6 dual cards and one single. It seems to be in place because most (all?!) BIOSes are 32bit which limits the maximum address space for all GPUs to 4GB. And that apparently is not enough to run more cards. The only system that is known to run 13 GPUs is Fastra2, but even for getting this to boot Asus had to chip in a custom BIOS which initialises ONLY the first single GPU card, the rest is done via a custom Linux kernel (64bit, obviously) which has no problems to initialise the rest of them. You could say if the kernel makes this whole thing work, why not use even more GPUs, but there seems to be a general upper limit to I/O resource allocation for all devices in one system, to make even 13 cards work they had to disable pretty much every onboard device they don't really need.
And the resulting system still seems to be unstable, so I guess until BIOSes are 64bit and I/O is up to the task we won't see something bigger than this.
http://fastra2.ua.ac.be/wp-content/gallery/fastra2/IMG_0430.JPG
INFRNL
03-17-2010, 09:15 PM
^^^ I think thats the article I read, cause thats the system they built and had to mod the bios to get it to read all the gpu's. Seruious computing from those gpu's for their use.
They also made a custom mount for all the cards; I think it turned out sweet. Hope they get their issues resolved
NKrader
03-17-2010, 09:45 PM
i think i just came.. alitlle..:eek:
WhiteFireDragon
03-30-2010, 10:18 PM
how is it possible to run all these GPU's with a single PSU? how is there enough 6-in pci-e connectors?
Burninator
03-30-2010, 10:26 PM
how is it possible to run all these GPU's with a single PSU? how is there enough 6-in pci-e connectors?
I think there are actually 4 PSU's. Those little boxes in the drive bays I think are PSU's dedicated to the cards.
acicula
03-30-2010, 10:27 PM
how is it possible to run all these GPU's with a single PSU? how is there enough 6-in pci-e connectors?
3 extra psu's in the 5"25 slots.
123bob
03-31-2010, 12:45 AM
OK, I have perhaps a noobish question to ask.....:eek: If you use more than one PSU in rigs like this, do you have to consider DC ground bonding between the various supplies? If not, how do you avoid issues with ground loop currents knocking out hardware, or is this even a consideration?
Why do I ask? In the world of high powered AC, ground loop currents can get people killed for maintenance. In this world, I could see some smoking hardware?
Thx,
Bob
Movieman
03-31-2010, 01:07 AM
When I was setting up this W555 rig I got a lot of good info from the benching guys here at Xs.
First thing they told me was no way in hell could any one PSU handle even two ATI 5970 cards and my two X5680's at 4GHz+.
The cards they told me pull 300w each, then the cpu's would be at close to 250w each. The cpu part I can verify as I've had a kill a watt on this system since day one. It shows between 605-625w being pulled from the wall depending on whether I crank up the 5-113cfm fans in the front of the case.
Just one hard drive and a 260GTX EVGA card(idling at 25w usage) in the system so you do the math.
To run those 3-295's I'd want an additional 1200w PSU of multi rail design while using a single rail 1200w for the cpu's..