So I sent my failing 4850 out for repair. I got a new one back. It games great at 50-70 fps in gta4 on max settings. Temps stay under 55 under load and everything seem fine. 8 hours later I wake up and the comp is off. No power failure or anything, its just off. When i turn it back on the monitor does not receive signal. KB does not stay lit so i dont think the comp is fully booting up. I replaced it with an older card and it did not work, re seeted it and it finaly booted. Replaced it with the 4850 and it booted right up no problem. i strarted some video editing and startded rendering a movie in hd and then started gaming on it for 3.5 hours stressing it pretty hard with no problems. (the video rendering dropped my frames to 20-40 in gaming, still pretty good). Cpu was cranking, gfx were cranking and the comp was running fine. next morning the comp is off. I disabled auot restart on error. There is not blue screen, not "you have recovered from a serious error". this is like the 5th day it done this (turns ff while at work as well by the time i get home). It always a pint to reset and i need to remove, try booting, reseet it, somtimes plug in the old card whichs oem times doe not work on the first try either. Th old card was always reliable. Id ont thin this is power related since it can game so well. shouldn't be temp since cpu and gfx are with norm limits.
Intel DP35DPM Socket 775 Motherboard
Intel Quad Core Kentsfield 2.4Ghz Q6600 CPU
Ultra 4096MB PC6400 DDR2 800MHz Dual Channel 2X1024