ATI Catalyst 10.7 vs 10.6 Performance Comparison
 

Catalyst 10.7 is great. Game smoothness and playability, for this test setup, has increased. Micro-stutter generally associated with multi GPU setups is not notable at all during our testing, which is an excellent plus. Silly Steam games such as Droplitz and Soduku are playable again. 10.6 to 10.1 made these games unplayable; we were unable to find settings that worked. Usability is more of the same; CCC still seems cumbersome to use, however things are where you expect them to be and do what they are supposed to do.

http://www.rage3d.com/articles/ati_catalyst_10_7/