Well I just recently replaced the VGA cooler on my x1900 Video card. From stock to the VF1 Plus. I did this because i thought my GPU was over heating when i played very simple 3D games (Team Fortress 2 specifically) While its playing the FPS is fine around 80-100 FPS but after a few minutes it would shut off my PC the fans would rev up and my monitor light would go from green to yellow. After I switched the temps are much lower... I get about 85 Fahrenheit after i switched (thats idle temp) BUT the problem still persists when i play any even mildly straining 3D game (HL2 Ep 2). The thing is im confused as to what the problem is because the HDD has been known to shut off when i access certain data sometimes. More specifically i reinstalled TF2 to see if that would work but instead it did the same thing but this time when i restarted the PC (by holding the power button as i do every time this happens) it "Strongly reccomended a disc check" i skipped because ive been through this before many times with this Hard Drive.. ANOTHER possibility could be the PSU because well its not the best in the world and ive read that this happens with low end PSUs (my PSU: Suntec 680 Watt ATX Power Supply support Serial ATA SATA) It is a very old HDD and that could very well be the problem but i could have installed the cooler incorrectly as i have never actually done that before. But im about 75% sure that i did it right!!! I also used CCC to test for artifacts and the display shut off.... =/ I hear music still playing in the background if the display shuts off in this way.. Please help me !!! Please... Help... im getting nowhere with this.