Problems with gtx 280 sli and vista 64

[Vmpwraith]

2 GPUS in Vista may also cause a problem/Bug. Check out the sticky to the fix.

Possible fix for some of you with Vista and poor Graphic Card preformance low Fps

http://support.microsoft.com/kb/936710
" When a DirectX 10 application runs on a Windows Vista-based computer that has multiple graphics cards, the computer does not use the secondary graphics card"

1. You have a Windows Vista-based computer.
2. The computer uses two or more DirectX-compatible graphics processing units (GPUs) in a linked configuration.
3. You are using a DirectX 10 application and driver.

In this scenario, the computer's graphics performance indicates that only a single GPU is being used.
CAUSE
This problem occurs because the operating system does not forward driver-render requests to the secondary GPU.

This may also be a problem. Anyway you can check it out. This problem will effect more than just running wow.

[kermitforney]

Possible fix for some of you with Vista and poor Graphic Card preformance low Fps[/url]

http://support.microsoft.com/kb/936710
" When a DirectX 10 application runs on a Windows Vista-based computer that has multiple graphics cards, the computer does not use the secondary graphics card"

1. You have a Windows Vista-based computer.
2. The computer uses two or more DirectX-compatible graphics processing units (GPUs) in a linked configuration.
3. You are using a DirectX 10 application and driver.

In this scenario, the computer's graphics performance indicates that only a single GPU is being used.
CAUSE
This problem occurs because the operating system does not forward driver-render requests to the secondary GPU.

This may also be a problem. Anyway you can check it out. This problem will effect more than just running wow.

Later in this article the solution is given and reported to be corrected in Service Pack 1.

[Phanes]

For what it is worth I am an IT consultant and build high end rigs on the side via word of mouth. I have had two of the same card and one monitor plugged into each, back before they made it so SLI could use two monitors, and saw massive performance hits. What was happening is the cards are swapping resources so while one is utlizing resources the other one is waiting. Even though we are talking 1000s of a second swaps it was still horrible results.

When Clients ask me about SLI I tell them to run a two monster cards like dual 295s for quad sli and a massive small format monitor like a 30 or 32 inch. If they want to run dual monitors just run one high end card like a 285 and a pair of 26s.

I have not done dual non sli video cards in about a year so it may be different today. I just know last time I tried back in 08 with a pair of 9800s the performance was horrible.