win XP Freezes..

I have a very annoying problem with Win XP freezing and I mean really freezing !!! there is no detectable activity at all.. The only way out of this is to press the power button and then reboot. There is not even an entry registered in the logs. Rebooting procedes as normal without any reference to the forced shutdow. I am running win XP Pro on an AMD Athlon in a DFI Lanparty board with 2GB of RAM. Other programs running are usually ScrapbookMax, Photoshop CS2, and Firefox. My security (also Running) is Trend Micro Internet Security 2008.
If any one has any ideas please help….. as I am really stumpped..Thank You..