An AMD (depends on processor) with 2.4 Ghz should be almost as fast as a Pentium 4 with 3 Ghz. And AMD 64 with 3.2 Ghz would be around as fast as Pentium 4 with 4 Ghz, I think.
Why do you think AMD processors are sold so good? They're as fast as the ones from Pentium, cost less and can be overclocked quite far in comparison to the Pentium processors.
