Actually, kinda proves my point. Aside from the 640x480 test, probably due to pci controller being on chip vs on mb. Can you see the difference between 450 fps and 568?
http://static.techspot.com/articles-info/452/bench/Overclocking_01.png
I play at 1900x1200 since thats what my monitor support is. single gts 580 goes from 92.3fps to 92.8 fps from 3.6ghz and 4.4ghz. Seems that the cpu bottleneck is somewhere between 3.1ghz and 3.6ghz as that drops to 86fps. note that the intel systems are both pulling ~92 fps
What makes you think going from 4.2 to 4.7 won't have the same results? As far as intel vs amd, there are a lot of games optomized specifically for intel and will always run better on intel systems such as starcraft II. I would almost bet that even if AMD improves ipc by 150%, they would still lose those "game" bechmarks.
Here is a single 6970, stock, oc, and intel. looks pretty much the same. jumps of a massive 1-2 fps between systems and between overclocking and not, on all 3 games.
http://www.overclockersclub.com/reviews/amd_fx8150/11.htm
I am more intrested in seeing some load time testing rather than straght FPS wich is video card dependent.