Reasons I think it is RAM related:
1) I set my memory timings to auto and I blue screened at XP.
2) HL2 gives datacache.dll as source of crash.
3) Memtest doesn't like my memory when it is set at auto.
4) When playing with memory settings I usually end up blue screening with a page_fault_in_nonpaged_area message.
Reaons I think it is HDD related:
1) Windows XP and drivers are on the Maxtor Drive and the games I am CTDing are on the Raptor. (not sure if this is a problem)
I don't think I have faulty hardware, as I have removed them and cleaned them of any dust particle, and they run fine by themselves. I never have any problems unless running these particular games. I havn't tried any other recent games that are ram intensive like these, but I hope someone can point me in the right direction at least. If you have similar specs, please help me out with memory timing, because I believe this is the problem.