Order of cards in SLI

[sid_freeman]

I know if you're running two video cards in SLI that have different factory overclock speeds, it's recommended to put the lower clocked card in the primary slot, forcing the second to become underclocked to match it. My problem is that the MSI card (950mhz) I have in the primary slot gets too hot (100C and over at times) from the lack of space and heat rising from the Gigabyte (1ghz) card below it.

So I've switched them and put the Gigabyte card as the primary and the MSI as the secondary. Hoping that the MSI card runs a bit cooler. I used MSI Afterburner to manually underclock the Gigabyte card to match the speed numbers on the MSI card. So the core gpu clock, shader clock and memory clock numbers match the MSI Hawk. Is that a recommended fix or is there some aspect of the SLI thing that I'm missing? I don't have the option of changing the core voltage on either card but do I need to change the voltages as well?

It seems to be running a lot cooler now. Both cards hover around the 75C-80C mark now depending on the game I'm playing. Whereas before, the gigabyte card would get to 65C under load and the MSI card 90C and above.

[Soultribunal]

No need to adjust the voltages on a Downclock.
The way you did it seems to be correct, I hate how they don't make External Exhaust cards in the lower Tier anymore. The Heatdump seems to kill these fancy heatsinks for then help them.

ST

[sid_freeman]

Excellent. Thanks for the feedback.

Yeah I was surprised at how big a temperature difference there was depending on which card was on top. I think I could probably stand to have a different case/fan arrangement to get more air moving. I have an Antec P180. I like it, but graphics cooling certainly isn't what it does best.

[cal920c]

I think you need a new case to exhaust the hot air better.

[sid_freeman]

Originally Posted by cal920c

I think you need a new case to exhaust the hot air better.

Funny you should mention this. I splurged and bought a Coolermaster HAF-X over the weekend. Man what a difference! Running 3DMark performance benchmarks, my gpu temps dropped by 10C-12C and my fans are spinning 20%-30% less....and that's just with the stock cooling of the HAFX.

Great case. Huge, but good cooling and lots of space.

[Soultribunal]

The Case always makes all the difference with the temps our hardware runs at.
Good to see you got a much better setup.

ST