Crossfire GPU temperatures between master and slave

amdgamer

Supreme [H]ardness
Joined
Oct 27, 2004
Messages
4,880
Hey guys, I wanted to ask you guys a quick question. I have been using MSI's Afterburner monitoring utility lately to keep track of my GPU temperatures when playing games or even when running benchmarks. I have two XFX 5850 Black Editions running in Crossfire as you can see from this picture. When playing games, I have noticed that my GPU utilization of both video cards are always between 98-99%, but the temperature of GPU 1(the master) is always about 6-10 degree C hotter than my 2nd video card on the bottom. Do you guys also have this same issue? I always thought that my 2nd video card should run hotter since it is literally sandwiched right there by the PSU. As you can see, I have a full slot open between the two crossfire cards.

pc2.jpg
 

PrincessFrosty

Supreme [H]ardness
Joined
May 6, 2009
Messages
5,905
It's all about airflow, having a hotter master card is typical of these kinds of setup, the lower card obstructs the upper cards intake somewhat, you've also got hotter air rising off the lower card. PSU's on the other hand dont really run hot.

it's nothing to worry about as long as both temps are within acceptable range the fans will adjust automatically to keep them both cool.
 

amdgamer

Supreme [H]ardness
Joined
Oct 27, 2004
Messages
4,880
Thanks, that is what I thought. With my PSU being a 950 watt, I figured it would also give off some decent heat. What I would like to know is how the folks who run those SLI and Crossfire setups without keeping an open slot in between manage to keep their temperatures under control. What I am finding is that Metro 2033 drives my GPU's hotter than any other game I have, and it causes GPU 1 to reach 84-86 degrees C while GPU 2 only gets to 80 degrees C. I have all the fans on auto so they seem to do a decent job. I am only running a very mild core overclock to 775(10mhz above the stock OC) as that is all the ATI Overdrive utility will allow me to do.

I would like to increase airflow inside my case somewhat, but it isn't possible as i've got a big mess of cables partially blocking one of the intake fans. You can see part of the tangle in the picture above. Unfortunately, i'm running 4 hard drives so it isn't easy to deal with this.......
 

J32P

[H]ard|Gawd
Joined
Mar 5, 2005
Messages
1,881
amdgamer, you're not alone. I've seen my top 5870 close to 30c hotter compared to the bottom card. It annoyed the hell out of me at first but I'm now getting over it since there is no way to fix it besides water-cooling.

fyi
 

W.Feather

Hard DC'er for Aug 2012 / Feb 2019 / Mar 2020
Joined
Nov 10, 2009
Messages
11,478
It's all about airflow, having a hotter master card is typical of these kinds of setup, the lower card obstructs the upper cards intake somewhat, you've also got hotter air rising off the lower card. PSU's on the other hand dont really run hot.

it's nothing to worry about as long as both temps are within acceptable range the fans will adjust automatically to keep them both cool.

+1, had the same thing in a build for a friend, but luckily the Antec 300 had decent airflow....allowing the temps not to get too high.....get higher CFM fans if you think you need more airflow.....
 

Rogue71

[H]ard|Gawd
Joined
Aug 25, 2007
Messages
1,311
yea my top card is about 10-20c hotter under load depending on the game.
 

amdgamer

Supreme [H]ardness
Joined
Oct 27, 2004
Messages
4,880
I'm glad to see that i'm not alone on this. It kinda scared me at first thinking that maybe the fan on the top card wasn't working well, but I guess I won't think anymore of it. So long as I leave the fans on auto, I suspect that they will do their thing to keep my GPU cool enough. I almost feel sorry for my Auzentech sound card which is installed in the PCIx 1x slot just above my top card. It isn't pictured in that photo I put above as it wasn't installed at the time, but that sound card literally sits with hardly any clearance from the backside of that GPU.

I was originally going to have it installed sandwiched in that open PCIx 1x slot in between my two graphics cards, but that would have probably been a really bad idea.
 
Top