Try the 12.11 Beta drivers, it whats I use on my 7990 6gb and saw a big improvement..
All the best Brett
HUUUGE Difference, Where I was getting 40 fps I am now getting 60-70 frames, Frames are where they should be now thank you very much. I also switched around some power cables and made sure it was plugged in 100% properly and sitting in the pci slot properly along with everything else. Frames are much better now, again I thank you.