Crossfire GPU load questions.

[kromosto]

I put an 280x next to my 7970 lightning they are all stock. Have a 3770k @ 4.25 16gb ram etc etc.

Today i don't know why but i see that bf4 started to perform bad even sometimes under 60. When i check with gpuz and afterburner i saw that gpu1 (7970) runs around %50 but gpu2 always %99. Can this cause this or this is a problem that i should fix? I disabled ulps or something like that but that doesn't solved this. also should i make them run at same clock speed manually?

i can score 6002 on fire strike extreme with this setup which is not optimized for benchmarking actually it isn't optimized for anything

[kromosto]

yes that was the source of the problem. i didn't changed anything but today it works just fine and gpu usages are nearly same.

[Mtemel]

you can cross fire r280/290 s with 7900 series gpu's? i thought they had to be same series i.e 7000 series

[STEvil]

they are the same