computer freezing

[paintballfreak66]

Hey Hey guys, im a member of the new TS clan on the site and im having some computer issues. just wondering if any of you could help me out. anyways, i built my computer about 6 months ago and ever since ive had it it would freeze about once a week and i never really thought about it. i just didnt think it was a big deal since it was the first computer i had built and all. but for the past three weeks it freezes like crazy. it just locks up whenever it feels like it and the cursor is frozen on the screen. i have to push the button on the case to restart it. i thought maybe it was overheating so as soon as it locked up once, i took off my CPU fan and touched the processor- it was cold. i replaced the motherboard- and got a sound problem with steam. so i took that back and put the old one in and reformatted but this time i never installed the drivers for my AC 97 integrated sound and it never froze but of course i didnt have any sound. i tried to disable the AC 97 in the BIOS and install a new sound card but it would freeze. so here i am today, i reinstalled the AC 97 and it started freezing again. but today it has only frozen in steam which makes me think when the CPU usage in XP task manager is high, it freezes. does anyone know what is going on?

setup:
ECS L4VXA2 motherboard
Intel P4 2.66 processor
AC 97 integrated audio
Xp professional
1.0 Gig of RAM
FX5200 128MB vidcard
ATX case w/ 350W power
3 case fans
1 heat sink CPU fan
and the power supply fan

tell me what else you need to know