Built new PC... Now crashes on all games

Hey out there, this has been killing me for the last few days:

I built a new comp this week with a bunch of new parts and some canabalized old parts from my previous PC. Installed Windows Vista, works for everything else but always crashes about 10-15 minutes into playing games (HL2, M2TW, WIC).

First I updated all drivers for the mobo, graphics card, HD audio, wireless networking. Also the BIOS on the mobo. Still the same problem.

I thought it might be a vista problem so I used this 94010 hotfix. Still the same problem.

Next I tried doing a dual boot with Vista and XP to see if I could play games with XP. Still the same problem in XP which makes me believe it is a hardware issue.

These are my specs-

New Parts:

Intel Core 2 Duo E6850 3.00GHz

XFX nForce 680i motherboard

EVGA GeForce 8800gts 640MB
Western Digital Caviar RE2 500GB 7200 RPM SATA 3.0Gb/s Hard Drive

Vista Home Premium 32-bit



Used Parts (All almost 3 years old):

2GB (4x512MB) CORSAIR XMS2 512MB 240-Pin DDR2 SDRAM DDR2 533 (PC2 4300) Model CM2X512-4300C3

Antec TRUE550 ATX 550W Power Supply (this had a 20-pin instead of 24-pin connector, a 4-pin instead of an 8-pin CPU connector, amdI used an adapter for the pci-e 6-pin power)

Western Digital Raptor 74GB 10,000 RPM Serial ATA150 Hard Drive

Western Digital Caviar SE 250GB 7200 RPM Serial ATA150 Hard Driv

Linksys Wireless-g PCI adapter WMP54G v4.1

SONY Beige IDE DVD-ROM Drive Model DDU1613

SONY DVD Burner Beige IDE Model DW-D18A

3.5" floppy



So I'm thinking the 2 most suspect things are the power supply (since it's old and doesn't have the expanded connections) and the RAM (since it's old and I've heard that Vista doesn't handle 4 ram dimms too well). However I don't want to dump another $200-300 without asking for any advice. Is there anyone out there who can help?