Topic: Two 7950 cards suddenly warmer? (Read 802 times)

Checked thermal paste/heatsink is still sitting properly?

I reinstalled drivers, didn't reinstall the OS, do you think that could make a huge difference? I did go from AMD to Intel, so I guess it wouldn't be to far fetched. And yeah all the voltages are the same, the only way to lower the voltage is in windows with afterburner, and I'd rather use Ubuntu so lower voltages arent an option right now.


My thermostat says 68 but I highly doubt that. The old design was tested though in an open room that I would say is a lot cooler. The cards were a lot closer in the first design and ran at 66c so I don't think thats it, I think it has more to do with the entire rig conducting heat, which I noticed it is, and quite a bit. Also the fact that its not in a closet, on the top shelf near the ceiling I think is the real killer.


Yeah I think you're right with that hot air evacuation. The fact that it sits 3 feet from a ceiling in a closet I think is creating a lot of extra heat/hot air with no where for it to really go, though I do have cold air vent right above it blowing on it.

I started trouble shooting further, if I run just one card by itself, it stays at about 64/65 so I dont think that throws out the OS reinstall idea. I think it works fine in that sense. I added a second card, both cards ran at about 72, so I deft think its a heat/space/fan issue. I added a third card and then came a lot of problems, the third one runs a little warmer then the other two at temps 78 78 82 then after >30 min one will go dead/sick from over heating.

I currently have all the gpu fans turned up to 90% to help. It helped a little.

I currently have little computer fans on top of all three cards and testing to see how it helps. right now I'm at 73 73 78 so that's not bad at all. I also took the vent off the ac duct, so that it blows straight down on the rig. I think adding a 12/15" honeywell fan well improve it a lot, but realistically how much could that fan help? not more than 5 degrees I would imagine.

I haven't even gotten to adding the other 3 cards for a total of 6. That should be fun...

I also want to move it to the floor and see what kind of temp improvements I get.

Also, is it possible that the heat sync from the cards touching the aluminum it's sitting on, in turn making the aluminum almost to hot to touch, keeping the cards warmer than they should me?

Thanks for all the input. 

When you replaced your MB, did you reinstall OS/drivers? Can you confirm that the cards are all running at the same voltages?

You need a fan blowing on those bad boys. The hot air has a longer evacuation path now. Revert back to your old design and lower your voltage.

what was temp outside before that and what is now?


try some fans few od 12cm to put behind the cards ...

also the cards are  too near each one ...

try to undervolt them...

So I had a pretty neat open air design for my x6 7950 rig, and all the temperatures stayed at about 66/67c but I wasn't satisfied with the design and wanted to re do it. Here is a pic of the old design.

http://distilleryimage1.s3.amazonaws.com/928e0168cef911e2bf3622000a9f1886_7.jpg

Not bad, but I could do better. So after many beers and a long weekend with some fellow engineers. I have this.

http://distilleryimage4.s3.amazonaws.com/e9f5f114dc9011e28cc022000ae80ec6_7.jpg

Borrowed the design on here from the thecryptokeeper

Anyhow, we were handling all the cards kind of rough I guess and the motherboard, in the process I either shorted the cpu or mobo or both, either way the damn thing wouldn't boot, it would come on, spit some LED Debug error, and the cpu fan wouldn't even crank up.

So i swapped out the mobo and cpu for the MSI z77 65 with a basic celeron processor, the notorious mobo everyone likes to use because it doesnt need a presence pin short and etc etc.

Long story short, I booted this thing up, re installed drivers and updates, made everything exactly the way it was before and I'm only running 5 cards right now, 6th one is buggy, but of those five 3 of them stay at 63,66,68 which is great. However these two other ones, are both currently at 80. Even though I have there fan speeds cranked up to 90% while the other cards only are at 70%.

Any ideas why on earth these temps are so much higher? Theres no way its running hotter in the new design, so I'm thinking maybe the heatsink came loose and I need to tighten the screws on the back of the cards? Or maybe fresh thermal paste?

Any insight and ideas are much appreciated!!!

Greg