Strange crossfire thermal behaviour

[eyetrip]

My top card is running cooler than my bottom card.

When I had a smaller board and the cards were right next to each other, the behaviour was what I expected - the top car ran a fair bit hotter.

Now I have a new board and the cards are spaced an extra slot apart, I still expected the top card to be a bit warmer.

I have this case, with 140mm fan mounted on bottom.

http://www.overclockers.co.uk/showproduct.php?prodid=CA-045-OP&groupid=701&catid=7&subcat=505

Now, I am thinking the side-bar thing is working great for the top card, but the bottom 140mm fan is a scythe kama running at full pelt, which should be more than enough to cool that bottom card more than top.

Had anyone ever seen the bottom card run hotter?

PS - both are running 1408 shaders currently.

 

[ooEy]

ATI / Afterburner reporting the cards incorrectly?

I cant see any reason why the bottom would be cooler, my top 5850 gets a fair bit toastier than the bottom even though they are spaced out and have a bottom and side fan installed.

The 140mm fan is pulling air in yeah?

 

[ashmanuk67]

Have you got both fan speeds the same? You never know

 

[eyetrip]

ATI / Afterburner reporting the cards incorrectly?

The 140mm fan is pulling air in yeah?

Well, I am assuming GPU 1 is top and GPU 2 is bottom, so hoping I am reading right.

The fan is definitely pulling air in.

Have you got both fan speeds the same? You never know

Actually, I suppose as they are on auto, it could be the fan speeds are different.

Will force both to same speed tonight and see what I get.

I know I should just ignore it, but it's the sort of thing that gets into my head and I have to figure out why it's happening!