I have a problem that win xp keeps hanging.

I just did a fresh install of win xp pro. I have a amd thunderbird 1.4, with 512mb of ram and a gf2, 32x burner, dvd drive and two 40 gig hdds.

It just seems to hang at random points. Some times when i am using it other times when i am not. I check the event log but nothing comes up in it. I have all the power and hibernate options turned off. Can anyone help please?