7970+280x crossfire low GPU usage

[area51wolf]

Recently i have purchased a new motherboard and received my 7970 back from RMA. I am having this issue where in most games i wont see full utilization of any of my GPU's. They will usually hover at about 50-60% in games and the temps are well within range. I cant seem to get full utilization out of my cards, i have tried all the 14 and up drivers. I have individually tested the cards and they run fine by themselves. They are both running in 16x slots. They will sometimes work at about 90% but very rarely.
Can anyone please shed some light on this?

Specs:
AMD FX-8350 @4.7GHZ
Gigabyte 990FX UD3 (revision 4)
MSI R9 280x (downclocked to 1000mhz)
Sapphire 7970
Corsair RM1000 PSU

 

[Ryan Souza]

Your cpu cant utilize both gpu's on top of the inherent problem with crossfire and most games.

 

[area51wolf]

Your cpu cant utilize both gpu's on top of the inherent problem with crossfire and most games.

I forgot to mention that I have had this setup running but with a worse motherboard than I currently have. I was using the asrock 970 extreme 4 and getting better fps than I am currently getting in BF4 with the gigabyte board. I have tested both the pci lanes individually and they seem to work fine. I understand that my current cpu will hold back crossfire capabilities but the weird thing is with the perf.overlay drawgpaph 1 it shows my cpu under the gpu line. The cpu should be above it if there was any sort of drastic bottleneck. I drop down to 35fps in some ares of siege of Shanghai and get the occasional 60fps

 

[area51wolf]

Update to the situation.

I have figured out what was wrong. It wasnt a CPU bottleneck.
I manually dialed in the voltages and core clocks to 1020 on both cards. looks like the 7970 wasnt getting enough voltage and crippling the system.
If you are running 2 different GPU's in CF i suggest you do the same and make sure that you un-tick the "Synchronize settings for similar graphics processors" option in MSI AFTERBURNER

This site also helped in the trouble shooting process and is a helpful guide to setting up CF
http://forums.overclockers.co.uk/showthread.php?t=18544020

 

[ZeusGamer]

Also a reminder, CF does not work in games that are set to play on windowed mode.

Plus, there are some games that really don't support CF. I.e Watch_Dogs, Assassin's Creed III, etc.

 

[ZeusGamer]

Your cpu cant utilize both gpu's on top of the inherent problem with crossfire and most games.

Where did you get this information? FX 8350 is a powerful CPU and yes, it can power two GPU's in SLI and three GPU's in CrossFIreX configuration.