For low framerates make sure supersample is not used with rf2, use multisample and the fps gain is huge.
The 7970 should be able to deliver, a single works for me. How did you update the Catalyst???? I use ATI man uninstaller, and follow up with...
I run an ATI 7970 with triple's. With the new build I had to turn Supersample to Multisample in the CCC. The frame rates went from 40 FPS to 140...
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