Poor 6850 crossfire & eyefinity performance in BC2

I

ichbingottderliebe

Limp Gawd
Joined
Dec 1, 2004
Messages
173
Hi all,

This is my 1st post on here, it was recommended to try over here for help.

I have 2 x 6850's in crossfire and I run eyefinity.(5040 x 1050) My problem is in Bad Company 2 the performance is terrible. Even on low settings I get around 25 fps and high I get 20 or less. But if I disable crossfire and run just one card I can run 5040 x 1050 and settings on high with AA and anisotropic. I usually get between 40-60 fps


So what is the deal? I did a fresh install and I am running 11.1a drivers and the current crossfire profiles. Is it a driver issue? If I benchmark the system runs great, it scores a lot higher than a single card.

Any help would be appreciated, or pass this along to ATi so they do a BC2 profile update.

Thanks
 
my 6850s have been working fine in BC2... I just installed 11.1a and haven't played using that driver set, but when I played with (I think it was 10.10e) it ran great will all settings maxed. I wasn't using eyefinity though...
 
I have been using Cat 10.10 and all has been awesome at 1920 X 1080 thru HDMI, mainly because the others ran kinda shitty in a real bad way. They were making my old 4850's look real good again until I used Drive Sweeper and then manually deleted all the folders on the hard drives, rebooted back into Windows and reinstalled them again. Ran like a champ after that. But like the last poster I haven't jumped off into Eyefinity yet either.
 
Sorry guys, the game runs great not in eyefinity. On a single monitor 1920 x 1200 (one is a 24'') it runs like 100 fps with all settings on high. But that defeats the point of having 3 monitors. Of course I haven't tested 1 monitor with crossfire and with just one card to see what FPS are.
 
You have 1GB cards... That isn't enough to run Bad Company 2 at 5760x1200. Maybe not 5040x1050 either.
 
samuelmorris said:
You have 1GB cards... That isn't enough to run Bad Company 2 at 5760x1200. Maybe not 5040x1050 either.
Click to expand...

So vRAM suddenly stops being the bottleneck when he disables crossfire and runs one card at that reoslution?

Nah, definitely something odd there. How are your other games doing at eyefinity resolutions with crossfire as opposed to just one card? And how are the temperatures, GPU utilization and clock speeds when playing BC2 in crossfire mode? You can use GPU-z to monitor it.
 
Rare cases perhaps. But note that he's getting 25fps crossfired on *low* settings, while getting 40-60fps on one card with *high* settings. Going from low->high should more than make up for any vRAM overhead from using crossfire.
 
That's true, didn't spot that. Must be driver fail then, negative scaling in Bad Company 2 can happen unfortunately, especially with crossfire 6850s, which are more susceptible to it than other HD6 series in crossfire. Best I can suggest is try with 10.10e, 10.12a and 11.1a. One of them should work.
 
Snowknight26 said:
Pretty sure CrossFire (with any cards) is broken in BC2. For example, my 4850s:
Click to expand...

My 5870's run BC2 in xfire just fine, single and eyefinity (5760x1080). There are also plenty of benches showing crossfire works fine in BC2.

You have 1GB cards... That isn't enough to run Bad Company 2 at 5760x1200. Maybe not 5040x1050 either.
Click to expand...
Completely untrue. The only thing 1 GB cards have issues with is 4xAA or more. I see pretty good scaling from 5870 xfire and a single card can even run the game fine as the OP has demonstrated. If VRAM was the issue it wouldn't make sense that when he tries single card it runs the game fine.
 
Did you update the Directx runtime files? Before that I got like 15FPS all the time, after when I updated it it ran fine, except now that under Crossfire it crashes on me for some odd reason.
 
Yeah I have the latest DX files. Any else have any recommendations? If ATi knows about this, do you think they will fix it? What is the point of having crossfire and not being able to use it in eyefinity..its really the most important time since its such a high res.
 
ichbingottderliebe said:
But if I disable crossfire and run just one card I can run 5040 x 1050 and settings on high with AA and anisotropic. I usually get between 40-60 fps
Click to expand...

Are you sure you're getting that fps with one card with those settings? I have the same setup but with one card. I can barely maintain 75fps with everything set on low with 1x aa and 1x af. Vsync enable. My card's already being pushed to 99% utilization.
 
nxcess said:
Are you sure you're getting that fps with one card with those settings? I have the same setup but with one card. I can barely maintain 75fps with everything set on low with 1x aa and 1x af. Vsync enable. My card's already being pushed to 99% utilization.
Click to expand...

BC2 graphics don't scale *that* well (as in, low doesn't get a ton more FPS than high or medium). Also, always turn off Vsync if you want to refer to FPS... Personally I've found the best middle ground in BC2 to be medium since it looks pretty much like high (try it yourself and take some screenshots to compare) but it gives about 10-20% more frames which I like in MP games.
 
Medium looks nice but becomes unplayable to me. I rather have my fps sitting at 75 than for it to drop to 40-50. Gameplay isn't as smooth.
 
I have the exact same problem, i was hoping he'd got a solution.
CF enabled and i get ~20FPS on BC2, but when i disable CF the FPS suddenly jumps to ~65.
EDIT: forgot to mention, CF was working fine, the problem started about a week ago.
 
Raap said:
So vRAM suddenly stops being the bottleneck when he disables crossfire and runs one card at that reoslution?

Nah, definitely something odd there. How are your other games doing at eyefinity resolutions with crossfire as opposed to just one card? And how are the temperatures, GPU utilization and clock speeds when playing BC2 in crossfire mode? You can use GPU-z to monitor it.
Click to expand...

Multi-GPU setup take more VRAM than single GPU due to its nature..
 
Okay gonna throw this your way OP. Completely separate issue and game. But the problem could be related. I blame the driver.

GTA 4 and EFLC, the driver reports the wrong amount of vram when crossfire is enabled. I had the game telling me I had 4gb of vram and it didn't let me change resolution or anything. It took me 2 days to finally fix and troubleshoot the issue. Again if I disabled crossfire on 10.12a or 11.1a it would work fine and show 2gb with crossfire enabled it would show 4GB. The game also ran worse with crossfire than without. This issue was fixed a few driver revisions ago and then reintroduced since 10.12.

I had to add a command to the target of the gta4 and eflc executables to say -availablevidmem 0.50. Once I saved that and launched the game, even in crossfire It showed 2gb and I could adjust resolution and everything.

So perhaps OP's crossfire setup is suffering the same, however in his case the driver is reporting 2gb to the game when he actually only has 1gb. Unfortunately if you were wondering who the one person in the world who doesn't play bfbc2 is then you have just found them. OP if there is a way for you to test this I'd suggest you try it. I'm sure there are console commands you can type just like in most other games.

Might fix your issue.
 
I couldn't get more than a 50 fps avrg w one 5870 at 4800x900 on medium with no aa. Getting 100fps at a higher res w/ high settings and AA? Lol. I would say that when it says crossfire, it is actually running on 1 card and when single, crossfire is enabled.
 
I'll try what lord exodia suggested. With the new 11.2 drivers out and 11.2 CAP3 profile, I was hoping it would fix the issue. I uninstalled the old, ran driver sweeper and cleaned it all up. I rebooted it came back in the standard low graphics mode. I installed the 11.2, rebooted and installed the CAP 3 profile.


So in BC2 under eyefinity it runs even worse...around 14 fps on low. And there are graphical glitches now.



Flopper so you play on low settings & DX10 with crossfire and eyefinty? I would think that basically is a waste of the card.

I still don't get it, I can play on high settings with 1 card and 5040 x 1050 and it runs awesome. Easy 30-40 fps still.
 
Try testing out each card to make sure you don't have a bad one.
 
Ok I tried what Lord Exida said to do. I put that command into Steam under BC2 advance properties. And I still got terrible FPS.

I went to guru3d and found the CAP4 profile and installed that...same thing.

I took a few video's off my droid x and I am uploading them to photobucket. But you will be able to see that with crossfire + eyefinity I get around 20-30 fps on high. With just single card + eyefinity I get around 45-50 fps. (both on high settings 1x / 8x)

I posted on the AMD driver suggestion...so here is to hoping the do something about this.

And I haven't tested 1 card at a time..one could be bad. I'll test it out this weekend.
 
Here are some quick Droid X video's. The top one is in game with Crossfire enabled and you can see all settings on high. Around 25-30 FPS...with out barely moving.

http://smg.photobucket.com/albums/v281/jwright77/?action=view&current=2011-03-16_21-54-11_469.mp4

And here is in game with Crossfire disabled, settings are all the same. The funny thing is even loading the map it loads at like 150 fps, on crossfire it is like 6 fps. So something isn't right. Either way the 2nd Video is on 1 card, easy 40-50 FPS all on high, same settings ect..

http://smg.photobucket.com/albums/v281/jwright77/?action=view&current=2011-03-16_21-54-44_312.mp4
 
You guys seem to be forgetting about the Crossfire bridge bottleneck:

The crossfire bridge that all AMD cards use today is only 900mbits/sec. Apparently it only has enough bandwidth for a total resolution of 2560x1600. That's about 4 million pixels. Your 5760x1080 resolution is trying to move 6.2 million pixels.

This is not a problem for the two GPUs inside a 5970 as they communicate via the CrossfireX Sideport, which has a bandwidth of 5.0 Gbits.

569px-R700_interconnect.png


This means that, when running Eyefinity, you will be better off with a single 5970 than two 5870 in Crossfire mode. Otherwise the communication between the two cards is bottlenecked at the Crossfire bridge level.

Quoting from this article HERE:

"Generating that many pixels at the right quality levels would tax any single graphics chip. Making CrossFire work on this scale presents some challenges, however, as AMD readily admits. The core issue is the fact that the dedicated CrossFire interconnect used for passing completed frames between cards has "only" enough bandwidth to sustain a 2560x1600 display resolution. Even three 1080p displays will exceed its capacity. The alternative is to transfer frame buffer data via PCI Express, which is what AMD does when necessary. Using PCIe works, but it can limit performance scaling somewhat—don't expect to see the near-linear scaling one might get out of a dual-card setup in the right game with a single display. That's not to say mixing CrossFire with Eyefinity won't be worth doing. Based on AMD's performance estimates, frame rates could improve between about 25% and 75% when adding a second GPU with a 12-megapixel, six-monitor array."

Second, there is a memory limitation. The 1GB cards don't have enough memory to run Eyefinity in high resolutions with high AA settings (I think the new MLAA setting in the latest drivers *might* help here).

I also suggest you read what Callsign_Vega came up with on his trials with TRI/QUAD 6970s and TRI 3GB 580s HERE. Lots of information there.

I wish I had known about this before getting a 5970 + 5870 in tri-crossfire for my 3x30" monitors. I reasoned that if two GPUs are good, three would be even better to handle three 30" monitors. Big mistake.
 
ichbingottderliebe said:
I'll try what lord exodia suggested. With the new 11.2 drivers out and 11.2 CAP3 profile, I was hoping it would fix the issue. I uninstalled the old, ran driver sweeper and cleaned it all up. I rebooted it came back in the standard low graphics mode. I installed the 11.2, rebooted and installed the CAP 3 profile.


So in BC2 under eyefinity it runs even worse...around 14 fps on low. And there are graphical glitches now.



Flopper so you play on low settings & DX10 with crossfire and eyefinty? I would think that basically is a waste of the card.

I still don't get it, I can play on high settings with 1 card and 5040 x 1050 and it runs awesome. Easy 30-40 fps still.
Click to expand...

max out fps is a must in a shooter.
cant stand delay due to low fps or u die.
other games I play with other settings.

I tried 6950x2, with maxed out settings, framerate dropped to much for playability for me.
soon golf season opens up so gaming goes to rest.
 
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