Quake 3 is completely different in this respect. This game just loves CPU power. While the Radeon and GeForce4 returned almost identical results on a P4 1600 MHz, it took the jump to the P4 2.53 GHz to unleash the Radeon's full potential and let it stretch its legs.
3DMark 2001 SE
The 3DMark 2001 SE score is influenced both by the CPU and the video card - which makes sense, since it was designed as a system benchmark.
So, a fast CPU doesn't necessarily guarantee a better end result. Or the other way around: a faster video card won't necessarily give you higher frame rates - at least not in low resolutions. In plain English: if you're considering buying a Radeon 9700, you should ensure that the rest of the system can keep up with it.