Poor Performance with 6950 crossfire

CG_Gamer

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Aug 30, 2010
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I own a pair of MSI Twin Frozr II 2gb 6950's and I dont think im getting the performance that I am supposed to be getting at my resolution.

i game at 6024x1080 (bezel corrected) and from the benchmarks ive seen im supposed to be getting just a tad better performance than a 7970. But when i boot up Dirt3 or BF3 I have to start turning settings down ( much more than normal)

I havent the slightest clue. Im using the latest 12.7 drivers and the crossfire profiles on the drivers page

I dont think its a bottleneck or a power supply issue but here are the spec anyway

2600k 4.5ghz

Rosewill 950w
http://www.newegg.com/Product/Product.aspx?Item=N82E16817182097





ANy help/enlightenment with the issue would be greatly appreciated
 

TokyoTom

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What kind of performance are you expecting (in terms of settings/FPS)?

That is a pretty big resolution, but I would think you you could handle Dirt3 just fine with everything maxed. Battlefield is another story though.

Do you have AA enabled in BF3?

I run a resolution of 2560 x 1440 and have two 6950s in crossfire (1GB versions), and enabling AA absolutely kills my performance. Turning it off allows me to run things nicely with everything on ultra for the single player campaign mode but in 48-64 person multiplayer maps things really start to slow down. Sometimes FPS dip below 30 FPS. It seems that changing video settings to "automatic" gives me the best performance. This gives me a mix of ultra and high settings (mostly high) with no AA enabled and everything looks great and runs smoothly.

However, I am a little disappointed with performance as well. When cranking up the graphics I use the on screen display in Afterburner to monitor GPU usage and very often the crossfire scaling in BF3 is terrible. It is very inconsistent. Sometimes I get both GPUs operating at 90-95% putting out a consistent 60 FPS (or more with vsync off), but a lot of the time I see that both GPUs are running at 50-60% and I'm only getting 35-45 FPS with dips below 30 when there is a lot of action on screen. My processor is holding me back a bit but you shouldn't be seeing any bottleneck.

Try the "auto" setting that allows the game to choose the best combination for your hardware and see how that looks. You may also want to turn off vsync. Did you try monitoring with an OSD to see if your GPUs are being fully utilized?

At 6024x1080 you are going to have to make some compromises and do a little tweaking. BF3 is a demanding game so with 3 monitors you are going to have to turn some settings down.

 

CG_Gamer

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no AA in BF3, did a little tweaking in Dirt3, turns out you really should restart the game after a major graphics change, so now im getting a solid 50 with 4xaa on ultra settings

but in BF3 its strange, at 1080p I can do ultra with 4xaa and record at the same time all at 60fps, but when I turn up the res I have to push everything to a med high low setup, both cards chugging at a nice 95% but that's in multiplayer, on singleplayer I can get by with High settings and AA so im not sure whats up

I think its the temps tho, my cards run extremely hot and I cant do anything to pull the temps down, 83C under load is way too high for my AMD liking, idk if they've improved but Nvidia was the only one for a while who could manage temps like that