Hi everyone, 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. any ideas? thanks Intel DP35DPM Socket 775 Motherboard Intel Quad Core Kentsfield 2.4Ghz Q6600 CPU Ultra 4096MB PC6400 DDR2 800MHz Dual Channel 2X1024

Suggestion only. Go into the BIOS under power management and disable any options to turn things off. Do the same in Windows. I'm not familiar with Vista, but in XP you can right-click the desktop, select the "Screen Saver" tab, then click the "Power..." button. Change "Turn off monitor" to 'never' and change "Turn off hard disks" to never. It may not help, but I had a computer that would not wake up properly and this solved the problem.

sorry for wasting everyone's time I am an idiot. I set up the high performance profile to never sleep and such but did not realize it was set to standby on the balanced profile that was actually selected. Basically the comp was idling itself to sleep. Since I never use sleep it is not set up right int he bios and thus had no way of waking itself up. I figured this out when it did not reload my gmail notifier asking for a password like it does on startup. I finaly realized it was not shutting down it was just going to sleep and putting itself into a coma. So rufus 42, you were right, but i was able to figure this one out on my own like 3 am last night. Thanks for your help. I thought it was my gfx card since that was a new HW change. I over looked that it was also a fresh install of the OS. Thanks for your help rufus. Intel DP35DPM Socket 775 Motherboard Intel Quad Core Kentsfield 2.4Ghz Q6600 CPU Ultra 4096MB PC6400 DDR2 800MHz Dual Channel 2X1024