Constant Freezes

Hi,

I have been having various problems with the game freezing. It either happens during a loading screen of a new location or when i equip items in inventory. The game becomes unresponsive (I only hear the sound) and I have to shut it down via task manager.
I haven't been able to play more than 15 minutes at a time. I tried a clean install of a different version of windows, but the problem remained.
I am running windows xp 32 bit, 3 GB RAM, GeForce 250 GTS.

Thanks for any advice.