Sapphire HD 6970 FleX Battlefield 3 Edition Review @ OCC
 

To speak more specifically about the Sapphire HD 6970 FleX Battlefield 3 Edition, I will say that none of the results are surprising or mind-blowing because we already knew what to expect. The Cayman architecture is no different than it was before, and the only thing we get with it are slightly higher out-of-the-box speeds and a superior cooler. No raw performance gains were expected and none were seen. In fact, in every framerate test that was run, both this Sapphire HD 6970 and the comparison HD 6970 stayed within a few frames per second, or about 5% ahead or behind. The advantage lies in the higher "stock" clock speed, in which case this Sapphire HD 6970 generally had a slight edge.

http://www.overclockersclub.com/revi...6970_flex_bf3/