New system locks up in games

[Yavitz]

Ok, heres the issue. Two months ago I upgraded my system. I bought a x1800XL a motherboard for PCI-E and a new PSU. I still havent been able to play any games with it. Every time I go to play a game it will lock up at seemingly random times in every game. It also locks up on CPU test 1 of 3DMark05 usually under 20 seconds into it. At first I thought it was the power supply I bought so I went out and got a better Antec. That didn't work. Next I tried switching my HDD's around that didn't work. In my most recent attempt I tried using my roomates RAM and that didnt work. I am totally lost here. Both GPU and CPU temps come up normal GPU around 65-70 under load, and CPU 55-60 under load. I have also tried many different sets of drivers and a newer BIOS. Does anyone have any ideas I've dumped so much money into trying to get this to work. My current specs are:

AMD Athlon 64 3400+ Socket 754
Asus K8N4-E Deluxe motherboard
ATI x1800XL GPU 256MB
2GB Corsair XMS RAM (2x 1024)
Antec Smartpower 2.0 500w PSU
WD 34GB Raptor
NEC DVD Burner
Windows XP Pro SP2

 

[-Metachronos-]

55-60 for an amd, that's bad.