Battlefield 3 inconsistent performance with Crossfire

[Guest]

Hi, I just got another 5870 to Crossfire with

When I play BF3, it will be running at 50-70, but it will frequently have bursts of really low framerates for as long as 30-40 seconds at a time. However, the FPS counter in the corner indicates just a drop to 30-40 fps, but I can feel that it is much worse, maybe 20 at best.

My system:

i5-2500k, 3.2 ghz (stock cooling/clocks)
ATI Radeon 5870 x2 Crossfire (stock cooling/clocks)
8GB DDR3 RAM
Gigabyte GA-Z68-UD3H-B3 motherboard
Hitachi HDT722525DLA380 (250GB - 7200 RPM) + Samsung HD161HJ (160GB - 7200RPM)
Windows 7 Ultimate 64 bit
1050W OEM PSU taken from an HP XW9400 Workstation

I have the latest AMD drivers and Application Profiles, 12.3 for both.

I am playing at 1900*1080, with everything set to max.

Help please!

 

[gary1]

PSU?

 

[Guest]

PSU?

Oops, added to original post.

It's an OEM 1050W PSU taken from an HP XW9400 Workstation from around 2008/2009

Hard drives are also from 2005/2006

 

[bumnut53]

Lack of video ram, BF3 needs more than 1 GB video ram to play on max settings.

 

[13thmonkey]

+1 ^

However to start to get some proof, does the same thing happen when you drop the settings to a low level? if it does then its a CPU problem.

 

[Stupido]

Lack of video ram, BF3 needs more than 1 GB video ram to play on max settings.

on ultra yes, but on max 1GB is enough...
my setup is 2x6850 and never got any problems on 1920x1200 - all smooth & nice even in busy areas...

 

[casualcolors]

I feel like people should just stop saying "max settings" if they aren't going to accept that max settings means every setting turned to the highest possible value and at least 4x multisampling.

I do agree with you otherwise though. 2 5870's should not be having any remote issue with playing BF3 on high. Does the game perform more smoothly with crossfire disabled?

 

[Guest]

I feel like people should just stop saying "max settings" if they aren't going to accept that max settings means every setting turned to the highest possible value and at least 4x multisampling.

I do agree with you otherwise though. 2 5870's should not be having any remote issue with playing BF3 on high. Does the game perform more smoothly with crossfire disabled?

When I say max settings, I literally mean MAX settings. As in everything turned up to the highest it will go.

I believe it is a software problem, because it happens at random. During a huge fight scene with a lot of explosions, I will still be at 40-60 fps. After, however, it may randomly drop to 20 fps while just moving around/turning.

My friend has xfire 6850 with 1GB of RAM and he runs it all maxed out no problems.

 

[casualcolors]

When I say max settings, I literally mean MAX settings. As in everything turned up to the highest it will go.

I believe it is a software problem, because it happens at random. During a huge fight scene with a lot of explosions, I will still be at 40-60 fps. After, however, it may randomly drop to 20 fps while just moving around/turning.

My friend has xfire 6850 with 1GB of RAM and he runs it all maxed out no problems.

Do you have the anti-aliasing set as high as it will go? Because xfire 5870's won't play the game well with 8x MSAA or higher. You're pretty much limited to 4x MSAA (which visually is no different than 8x) with almost any hardware configuration in BF3 (and in most demanding games).

 

[Guest]

Do you have the anti-aliasing set as high as it will go? Because xfire 5870's won't play the game well with 8x MSAA or higher. You're pretty much limited to 4x MSAA (which visually is no different than 8x) with almost any hardware configuration in BF3 (and in most demanding games).

BF3 AA's max is only 4x.

 

[casualcolors]

BF3 AA's max is only 4x.

I don't use it personally, but even 4x is going to be a stretch when you fully saturate your VRAM. Do you have 1gb 5870's or do you have a custom model with more VRAM (note, 2 cards in crossfire does not equal double vram).

 

[Guest]

I don't use it personally, but even 4x is going to be a stretch when you fully saturate your VRAM. Do you have 1gb 5870's or do you have a custom model with more VRAM (note, 2 cards in crossfire does not equal double vram).

I have 1GB versions.

Does anyone have any software related fixes to try?

 

[casualcolors]

I have 1GB versions.

Does anyone have any software related fixes to try?

You probably just need to turn anti-aliasing down to 2x or off entirely. Your inconsistent hitching sounds like it's related to vram getting saturated. The game uses well beyond 1gb at 1920x1080 even without deferred AA. Sorry =/.