If you're running WoW in a xfire setup (mine in dual 7970s), the wow CAP profile provides very poor performance.
wow set to dx11, 2560x1600, everything ultra (or highest).
For example, when flying in Pandaria, my fps would very between 10-30fps. Older areas were better, but still very low given the power of the two cards.
If I create a new game profile, leaving everything set to default, but set the crossfire mode to "Optimize 1 x 1" the FPS goes up be a factor of two times or more. The same area where previous was 10-30fps, is now 70+. Under this new setting, older areas can hit as high as 240-280fps.
My point here is that the WoW cap profile appears to be broken, and it appears that this FPS problem goes all the way back to the early 12.x drivers. I'm running 13.4 now.