MSI KM2M Combo-L (VIA KM266 Chipset Based)
AMD Athlon XP 1800+/266 FSB
Apacer 512MB DDR PC2100 RAM 32x8
VGA Chaintech GeForce MX4400 SE 128MB 4X AGP VGA & TV-OUT
Creative Labs Sound Blaster Live! Dolby Digital 5.1
300W generic power supply
MSI DVD-ROM
NEC 1.44 Floppy
Hitachi/IBM 60GB 7200RPM HD

This system worked perfectly for about 6 months. Then, performance started degrading and the computer started crashing during gaming. After trying the other parts in different computers to ensure their working status, I sent back the motherboard in exchange for a new one. This didnt help. I reapplied thermal paste on the processor. This didnt do anything. I moved the PCI cards from beneath my GeForce to give it more air, and played with the case off. No luck. Now, after trying a more powerful and brand name power supply, and after a complete reformat (to Windows 98 SE), the system is worse than ever. I have been without games for 6 months and now that it's summer I'm going crazy. Any help you can think of is greatly appreciated.

Thanks,