Graphics: 500 MHz Vs. 550 MHz

[Soleron]

Clock speed is just one part of what makes a graphics card perform well, and not even the most important. Number of shaders, design of shaders, memory bandwidth, driver design, code optimisation are some other factors.

Look at a (Prescott) Pentium 4 3GHz versus an (Ex) Athlon 64 2.2GHz. The Athlon is clearly faster in benchmarks, because on each clock it can execute more instructions.

The consensus seems to be that the 360's GPU is faster. But you will be able to find certain games, or certain benchmarks, where the PS3's GPU is faster.