6950 Crossfire SLOW FPS

dw1979

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Aug 4, 2007
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Hi Guys,

I'm running out of ideas.. I'm getting really low FPS in games but speed are good if I enable only 1 card.

I tested both card 1 by 1 for about 10 days each to make sure everything was fine.

3D Marks 11 Score with default settings:
P 7431 (Crossfire)
P 4618 (1 card)

Everything seem fine in 3dmarks.. lower then I expected but at least i know the crossfire work.

I tried latest Ati drivers 11.1 (with 11.1a hotfix & profile 10.12cap2 )
I tried earlier version 10.11 with hotfix & old profile ..
Crossfire is enabled in CCC.
Update my BIOS to the latest version.

Tried 3 different bridge for the crossfire.

I cleaned the drivers, reinstalled, tried a new Windows 7 install on a different HD & on a VHD.

Crossfire enabled in CCC.

Same results.

Crossfire All resolution at 1920x1080:

Dirt 2 - 60 fps average in the benchmark everything maxed
Mafia2 - 63 fps average in the benchmark everything maxed NO physx
Bad Company2 - 80~90 fps everything maxed
COD Black Ops - 70~90 fps everything maxed

1 card at 1920x1080:

Dirt 2 - 70 fps average in the benchmark everything maxed out
Mafia 2 - 56 fps in the benchmark everything maxed NO physx
Bad Company2 - 80~100 fps everything maxed
Cod Black Ops - 70~110fps everything maxed


My Spec:
MSI P55-GD55 (16x,4x bus lanes)
XFX 6950 2gb x2
i7 860 Intel
Antec Truepower 750W
G.Skill F3-12800 9-9-9-24 2x2gb
2x WD 500gig Black Raid 0

Everything Stock no O/C.


Something seem wrong.. but i have no idea what it is.. Unless it's the 4x lane on the second pci express screwing me up.. i don't have anymore ideas.

Please help.

thanks

Ben




 

z06psi

Distinguished
Feb 1, 2010
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18,810
Getting the same thing but with 5870's and I driverswept and reverted back to 10.12. 3Dmark vantage score was 28760 on crossfire so I know it is working but in games I am maxing out at 60-70. Seems very common.

In GPU-Z and CCC both cards are detected and all seems to be fine and I know they are working because of the benchmarking.

BTW my MB is showing X8 2.0 for both cards.
 

z06psi

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Feb 1, 2010
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Turned off Vsync in both CCC and the game (CODMW2). Frames went up to 70-90 but I am still getting very choppy game play. It only started after I did X-fire.

Can I disable X-fire in CCC and operate on only one card just to test that it is the X-fire setup?
 
While it sounds like vsync is on, looking at the motherboard I think that's your problem.

You need to upgrade to the MSI P55GD65 or equivalent. Your 2nd PCIe lane is at only 4x bandwidth which is definitely a bottleneck. You want at least 8x.
 

z06psi

Distinguished
Feb 1, 2010
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18,810
Any other ideas for me? I am running an Intel DP55SB which is a 1x16 2.0 or 2x8 2.0 PCI-E board

Before anybody says it is the power supply it is not. XFX black edition 850.
 


I don't know. I recommend you make a new thread instead of derailing the OPs.