[JagerbombXl]

Okay, well I've had this problem for a while now. First problem to discuss is that sometimes when i try to turn on or restart my computer the screen stays black and the computer turns on like it normally would. If and when I get past that sometimes my computer will freeze, The screen will freeze and if i had any type of sound running i would hear a buzzing through the speakers.This problem happens randomly, but most of the time when I am running a game of a type. I've tried a replacement video card and swapping the ram and such and no luck. I tried to reinstall windows but it freezes up before i can ever initialize it.
Heres my computer info.

Power Supply ( Standard Case Power Supply )
Processor ( AMD AthlonT64 X2 5200+ Dual-Core CPU w/ HyperTransport Technology )
Processor Cooling ( Certified CPU Fan and Heatsink )
Motherboard ( Asus M2A-VM AMD 690G Chipset w/6-channels, Gb LAN, S-ATA Raid, USB 2.0, Single PCI-E MB )
Memory ( 2048MB [1024MB X2] DDR2-800 PC6400 Memory Module Corsair XMS2 Xtreme w/Heat Spreader )
Video Card ( NVIDIA GeForce 8400GS 512MB w/DVI + TV Out Video )
ard Drive ( 500 GB HARD DRIVE [Serial-ATA-II, 3Gb, 7200 RPM, 16M Cache] )
Currently running SP1.
AVG 7.5
Spy bots Search & Destroy
Any help would be greatly appreciated.