Comparing processors is a rather in-exact science, IMHO. Many factors go in to determining the overall speed of a system. Like the cache, board, etc. In the case of comparing the PIII and the Athlon, the speed difference is probably too little to notice. It would be hard to tell even if you had both machines stacked up next to each other. You should look beyond raw speed when choosing. For example, most software writen today is still optimized for the Intel platform. And Intel's MMX extension is more popular the AMD's 3DNow... although 3DNow is gaining popularity...
Comparing two totally seperate processors like the G4 and PIII, which run seperate OSes, and are built around totally different philosphies, is next to impossible. There are just too many factors.
For example, I have a PII 300 and a G3 400. When running UT with the software renderer, the FPS is roughly equal. Why? Well, first of all, the the PC version has MMX support, which is a BIG help. The PC version has also been more heavily optimized than the mac version (well, I'm pretty sure it has), and the mac version is a PC port, and in order to keep things compatible, some sacrifices must be made.
On the other hand, the Seti@Home client runs well over twice as fast on the G3 than on the PII. Why? I'm not sure, exactly. I'm guessing it's because it's much easier to generate optimized code for RISC processors than CISC. The G3's excelent FPU may also play a role.
Er, anyhow, it's 2:35 AM and I'm dead tired and my brain has just halted all thought, so I'm gonna end it here. I know I've left some tidbits out...
BTW, I am NOT an expert by any means. I just have a lot of cross-platform experiance and know how difficult comparing different platforms can be. This is all based on observation, and not written fact. Ahh who cares... no one takes any of this stuff seriously anyhow...
Dustin
