system freeze

Hi a bit new to this but can someone help, my system will just freeze at random sometimes 3 or 4 times a day some days every minute the display just sticks and nothing else will happen until i restart it and it also reeboots for no reason every now and then. Im on my second motherboard, new HDD new memory 4 op installs and tried a different graphics card. my cpu dosent go higher than 53 degrees but im wondering if it is the processor thats locking up. system as follows
win xp media centre edition (clean install)
athlon xp 3200 cpu
gigabyte k7 trtiton mother board
pc3200 512mb 400mhz ddr x 2 at 400fsb
400w psu
winfast nvidia ti4200 graphics card
and on board sound

also internet connection 2meg can run hot and cold depending on how pc feels and i cant beleave i have written all this without it freezing any ideas or things to try cheers
dave

 

Have you run a memory tester?

Has the board got the latest bios upgrade? (don't try upgrading the bios till the system is more stable)

Looks like you will have to trouble shoot your hardware seeing as you have clean install.