Games Freezing

[KipDurran]

I just bought a new setup,

Athlon 64 3000
Gigabyte K8NS Ultra-939
1GB Samsung 400mhz pc3200 Dual Channel
550 watt power supply
PNY GeForce 6800 GT 256mb
Win XP Pro SP2
My games keeps freezing every few secs for a few secs. Seems like the intense ones like battlefield 2 and Far Cry. Installing programs causes it to restart.
Iv'e replaced the Processer, replaced the mother board, tried 8 different RAM sticks at different speeds, Tried different harddrives (IDE and SATA), different PS from 420 watt to 550 watt, tried a different video card.
I've also tried fresh formats with no other devices ( meaning just hard drive and video card), tried different video card drivers (newest, betas, and older), updated BIOS and all drivers.
I've been reading forums for the last week and a half. I'm at my wits end right now. Could someone please help me?

 

[zephead]

my friend had that same board, and he was experiencing similar troubles. it turned out that the board was at fault and replacing it fixed the problem. try running your machine using one stick of ram, with the case side panel off.

 

[KipDurran]

Tried that too.Thnx though.

 

[rrcn]

What are you temps?

What brand PSU's have you tried? Just because it's a 420w or 550w, it doesn't mean it's a reliable PSU.

What are you game settings at?