5870 Crossfire + Eyefinity problems

Fatal Except1on

Hi, if anyone here is running dual 5870s with eyefinity could you let me know?

I'm running my resolution at 6048x1200 with the two 5870s. I've tried running catalyst 11.4 as far back as 10.10 and get small variations in performance. However, in most games it is still poor. BFBC2 especially is laced with microstuttering.

It seems most games run fine with 1 GPU and not with two.

Anyone got any ideas? Also, its not a system issue as my components + PSU are all top notch.

lmimmfn

i havnt got 2 5870's( i run eyefinity with a single 6970 ) but have you tried the CAPs?

Fatal Except1on

Yep, tried latest cap (11.3 CAP5). Also tried older CAPs, still no go.

lmimmfn

what cpu do you have? micro stuttering is a common problem with dual card setups, sli/crossfire, however as i havnt seen the whole internet roaring about the problem you have with BC2( i know other games but still ), and youve tried all the drivers/caps i would guess its either a bottleneck on cpu or memory( again im only guessing as others dont get this ).

Could also be related to crap running in the background( 2 cards puts more strain on the cpu and stuff popping up in the background like antivirus progs can cause microstuttering ), also could be a psu issue with either cpu or gfx cards throttling.

*EDIT* erm, your resolution: 6048x1200? that will run like crap unless you have 2Gig 5870's? youre seriously short on vram for that and it will throttle the cards, reduce the resolution to about 3840x1024( just a test as i know that ran at about 50FPS maxed with my old 5850 OC'd with eyefinity in BC2, without AA ) and see if it removes the microstutter, i would bet the bank( not worth much i know lol ) that that is your issue and basically why i flogged my old 5850 for a 6970 because eyefinity needs LOADS of vram.

1 card may seem ok due to lack of vram but the problem is made worse with 2 cards as theyre both throtteling each other, i think you should confirm if its a vram issue, use no AA, use a resolution of 3840x1024 to test, then start increasing the resolution to your max, but do not enable AA

Fatal Except1on

Processor is an i7 930, mobo is a Rampage II Extreme, RAM is 12GB of OCZ Reaper, so it most certainly isn't a bottleneck.

On one card: Bad company 2 runs in 6048x1200 with everything max, AA off, and I get on average 50-60fps (with vsync). So it sure isn't a VRAM issue.

With two cards, crossfire enabled, I get 30/40 fps and microstuttering.

PSU is an Antec 1000w, so power is good. Rails are balanced. Temps are fine on card + elsewhere. It's not just in BC2, its in other games too like L4D2, TF2, etc.

Doesn't make sense that enabling crossfire results in half the performance of 1 card.

lmimmfn

Fatal Except1on wrote: »

Processor is an i7 930, mobo is a Rampage II Extreme, RAM is 12GB of OCZ Reaper, so it most certainly isn't a bottleneck

overclocked to 4Ghz or stock?

Fatal Except1on wrote: »

On one card: Bad company 2 runs in 6048x1200 with everything max, AA off, and I get on average 50-60fps (with vsync). So it sure isn't a VRAM issue.

i dont know how you could achieve 50-60FPS with 1 5870 at that resolution regardless of AA being off or not.

Either way, im guessing you only have 1Gig 5870s so thats pretty useless for high settings on an eyefinity setup @ 1080P or above.

Fatal Except1on

I did have the CPU overclocked, but it is now back at stock.

I have 1GB 5870s, and yes, a single card does indeed run BC2 at max settings, AA off getting 50-60fps.

lmimmfn

Fatal Except1on wrote: »

I did have the CPU overclocked, but it is now back at stock.

I have 1GB 5870s, and yes, a single card does indeed run BC2 at max settings, AA off getting 50-60fps.

i have my 920 at 4Ghz, i have 9 Gig of ram, overvolted and OC'd my old 5850 would beat stock 5870 performance, multiplayer it would only just about average 50FPS with vsynch off @3840x1024.

Either way, can you just reduce the resolution for your crossfire setup( as a test ), seriously you dont have enough vram.

Fatal Except1on

I don't understand. VRAM is not an issue. If it was, I would have problems running 6048x1200 on a single 5870. I, however, do not.

So if 1 card by itself can handle 6048x1200 with high FPS and no problems, how is it a VRAM issue?

Theoretically, if I have crossfire enabled, I should get an extra boost in performance, not the complete opposite.

EDIT: I lowered the resolution, it increased fps by 5-10, but nothing exceptional. Problem is still there. Also, I know that with crossfire enabled, my VRAM does not double, etc. But the whole thing just doesn't make sense. Stupid ATI drivers.

lmimmfn

ok, before anything ill just say you dont have enough vram in those cards for the resolution, i mean it doesnt matter what is done its just not going to work. If my 5850 was crippled with vram at 3840x1024 then those cards are going to be the same, and worse at any resolution higher than that.

Do those cards perform giving a 60-70% boost without eyefinity? my guess is they do.

1 card is throttling on vram, add another and they will throttle as per a single card but also throttle each other.

You cannot run that resolution with those cards, enquiring and drivers and what not isint going to fix the problem that your cards are ending up transfering textures and stuff from the cpu's memory more than theyre actually rendering stuff.

Like i said i had a 5850, i know the max resolution capable with that card and its vram and its half what youre running at( and it was performing as well as 1 of your 5870's ).

Fatal Except1on

lmimmfn, thanks for reply.

I'm still confused, I don't see how you think it is a vram issue.

If I use only one 5870 I can run the game PERFECTLY at 6048x1200, with no problems whatsoever and get very smooth framerates, contrary to what you think.

There has to be some other issue.


EDIT: Feck it, I think I'll just buy a 6990

lmimmfn

lol, a 6990 just like that? wish i could.

Before you go ordering can you check if you run BC2 in windowed mode if its still the same? and i assume you have catalyst AI switched on?.

If you are sure that the FPS are always the exact same with 1 or 2 cards then it just looks like crossfire isint enabled, hence trying windowed mode/catalyst AI.

Not enough vram when running crossfire can seriously hit scaling and thats all i really ment above.