I didn't really say that vernong. If you look at your final score, at the bottom, it's split into three categories:
-SM2.0 Score
-HDR/SM3.0 Score
-CPU Score
The top two test out your GPU and the last one tests out your CPU, so it's 2/3 graphics card benching and 1/3 CPU benching, as far as graphics processing's concerned.
The point I wanted to make is that if the cpu was literally bottlenecking your graphics card, then your SM2.0 and HDR/SM3.0 scores would suffer, however, if the game is particularly CPU-intensive, it doesn't matter what you set your graphics settings to, you'll still get poor performance, for example, with my old P4/512MB-PC100/9600XT system, I maxed out in CS:S at 20 fps whether I was maxed out at full res in DX9 or running 640x480 with low-settings in DX7, because my P4 and old ram just couldn't handle the physics and computing other aspects of the game. The graphics are really just a facade to the skeleton of performance which comes down to your cpu. In a sense, both situations would be considered bottlenecking, but with completely different reasons. In one case, it may vary from game to game, whereas in the other case, it will bring limitations to any game you try and play (like pairing up an 8800GTX with a P4).