my pc spec is
processor: amd athlon 2400xp
motherboard: ECS KT600-A
memory: 256mb pc333
video: mx440se 4x

my problem is, when is when i ran a program, my cpu usage is almost 100% while the free memory is still more than 75%.

though i just format and re-install the windows this is still my problem.

example is when i play winamp (mp3 files in the harddisk) and i run/explore the cdrom or even run the microsoft word. The sound is slowing down.

i can not determine if the problem is in the FSB of the motherboard or the CPU or increase the memory.

plese suggest anything to lessen my cpu usage.