Low FPS with 7950 Crossfire

[WoodenKiwi]

Hey guys, been poking around about this a few places but I figured the more input the better.

I recently picked up a second 7950 and got crossfire going, and I've finally gotten around to doing some in game testing. The results have unfortunately been troubling.

In Metro Last Light I'm getting around 30fps when previously I was getting around 60fps on a single 7950. Saints Row IV seemed like it always ran just fine on a single 7950, whereas now I'm getting about 25fps while flying around the city. Final Fantasy XIV ARR, while it doesn't technically support crossfire, is giving me 22-30fps.

Just about the only game I am seeing decent performance in is BF3 set to ultra, which gets 65fps consistently, but from what i hear that should be much higher.

The cards are dual Sapphire reference 7950s on the 7970 pcb and overclocked to 1100mhz clock/1550mhz memory. My processor is an FX-6300 overclocked to 4.4ghz.

Drivers are Catalyst 13.5 Beta 2, I have also tried 13.10 beta 1 with the same results

So far I've been told my FX-6300 may be the root and just viciously bottlenecking the cards, but I sorta feel like even if that's the case, my fps shouldn't be so low and I'm worried something else might be broken or setup incorrectly. If I can solidly be convinced it's the CPU i'll order an FX-8350 this very minute.

Anyone have any inout? Thanks all.

 

[bamato]

What % are the cards running during gaming? Temps?

 

[WoodenKiwi]

I will be running some checks tonight and get back to you. Any suggestions on testing software to use? So far I plan to be running GPU-z, HWmonitor, and HWinfo during a few games of BF3.

 

[bamato]

Those should work fine. I've used MSI AB as well to graph temps/voltages/etc.

 

[Supertrucker]

Are you overclocking without disabling ulps? Some driver versions leave the second card stuck at 100% load if you overclock without disabling it, and it will bring frame rates crashing down.

The sensors tab on gpu-z will show it.

Edit: will show if the second card is glitched and stuck at 100%. Would need to do a registry edit or use msi afterburner/sapphire trixx to disable ulps.

 

[Craxbax]

I also have two Sapphire HD7950s in xfire. Your cards are throttling and underclocking themselves. Had similar problems using CCC to overclock and not disabling ulps. One card was running at 500 core. I used the TRIXX to OC and there is a setting to disable ulps in TRIXX. I don't know about MSI AB but there are a lot of post around on how to do this manually. My BF3 is around 120-150fps ultra setting w/OC'd to, 1150/1500. 3dMark11 score was 15000+. During long gaming sessions I noticed occasional artifacts and my VRM temps in the 80s. My CF case has poor air flow so I reduced the OC to 1100/1425. Framerates in BF3 still average over 120 and 3dMark11 score P14600+.

 

[ATMINSIDE]

Have you tried the new GPU by itself?

 

[CerebralEdge]

I have 7950 crossfire with an FX-6300 and I have similar problems. I'm using CCC but I have not disabled ulps. I'll look up how to disable it for sure if it improves performance.

I noticed it specifically in Counter Strike: Global Offensive, I would get over 200fps with one 7950 and around 25 with crossfire enabled.

I downloaded Catalyst 13.10beta and it resolved itself. I'm sure a lot of it has to do with drivers.

 

[zdvil]

Hey as mentioned above, part of the issue may be driver related. I know that the 13.8 and 13.10 drivers have frame pacing which helps with the smoothness of gameplay. I'm not sure if the 13.9 drivers have this feature though.

 

[Craxbax]

I don't think 13.9 has frame pacing. 13.10 doesn't have it for Eyeinfinity.