Zeeman,
If you think something is wrong with your system take a test and compare. In some tasks, like textures AMD seems better. I suppose Intel is better when HT procs are used and AMD XPs are equal to non HT Intels, also look at the price tags when you compare.
I haven't run this yet but probably will--->
http://www.blanos.com/benchmark/index.html
Scenes are at ProgramFiles\LW \Content\Classic Content\Benchmark\
Post some your result if you want and I will post mine with XP 2500 plus at 1833Mhz *if I remember default speed right.