i noticed that a lot of people have been bandying about apple’s (silly) claims on g4 performance, so i decided to find out what was going on. jc has a xplatform comparison which summarizes the performance specs that have been published thus far. one important thing to note is that the specbench numbers for the g4 (450) are about half or the latest athlon/cumine chips. this number is also published by motorola (pdf). now, according to the specbench:
The G4-450 gets 21.4 20.4
The P3-866 gets 41.7 41.5
The Athlon-1000 gets 42.9 42.9
how then to explain the g4 numbers posted by apple? well, the answer lies in the little link that they give you. the numbers give by intel are for representative performance for programs calling the intel signal processing library, quite different from writing your own optimized routines to accomplish a task. assembly routines vs c/c++ called library performance. big difference. apple and oranges one might say. (granted altivec simd is cool, and works great for ffts)
now, there are good reasons for getting a mac, or a mac cube even, but frankly, performance or price, or price/performance are not among them. note, that while the former may not necessarily apply to the pc, the latter two most definitely do.
in my searching, i also came across a slightly dated (and slightly suspect), but very interesting architectural comparison of ppc vs x86.