HD 6950 CrossFire problem

arjenboerdijk

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Sep 16, 2011
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Hello,

A buddy of mine has got to Sapphire HD 6950 graphics cards configures for Crossfire setup. He's got a strange problem, and I'm trying to help him. His motherboard is a MSI Z68A-GD65 (B3), i5 2500K 3.3 GHz.

His problem is, that there is barely an FPS increase when running CFX versus no CFX. For example in F1 2011, he gets 63 FPS with one card, and 67 FPS with two cards. Shouldn't he be getting much much more FPS with a CrossFire setup compared to a single setup or is this normal?

What are your suggestions? Could it be one of the cards, his motherboard, or maybe the CFX bridge?

Thanks in advance,

Arjen
 

arjenboerdijk

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Yes he did. I'm now asking whether he has got the newest drivers. Just wondering if there are any settings in the BIOS that he has to change. He says that when he looks in CPU that, that his GPUs in CFX are running at 8x, and at 16x with only 1 card. Is this normal?
 

ringzero

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Updated drivers might help, but I doubt that's the problem. but he should definitely update.

I just hooked up Crossfire literally last night. It was as simple as plugging the new card into the PCI-e slot on my motherboard, connecting the new power cables (did he do this?), and connecting the Crossfire bridge.

Yes, that's pretty standard with Crossfire-ready motherboards. It's 16x on a single card, then 8x when two are plugged in. The speed difference between 16x and 8x are pretty small and should not be the source of his problems.
 

arjenboerdijk

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So it's normal that his FPS difference from singel card vs two cards is so small? He says that this is a flaw of the Sandy Bridge chipsets. Is this true? Does SLI also have this? If so, why would you want to run SLI / CFX anyway!?
 

ringzero

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Ordinarily no, it's not normal for it to be such a small difference. In a properly working Crossfire/SLI, you won't notice much of a difference between 2 cards at 16x versus 2 cards at 8x, that's all I meant.

As for the small difference, it depends on the game. Obviously not all games can utilize Crossfire. That said, take a look at this thread...

http://community.codemasters.com/forum/f1-2011-tech-game-support-1420/479257-question-work-crossfire-f1-2011-a.html
 

slhpss

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make sure he has the CF profiles installed too... with the driver updates AMD releases CF profiles as a separate download and if there isn't a profile for the game the system will default to using a single card.