I've tried to troubleshoot my way through this, but find myself too frustrated with my own machine to think straight. Any help would be greatly appreciated.
The problem started with my monitor (seemingly at random) going into power saving mode. I wouldn't be able to bring it back out of power saving mode without doing a complete restart of my system.
I suspected either the video card (ATI Radeon x1300 w/256MB) or the monitor (LG LCD). I tried a different monitor and had the same problem. I tried switching the connection from DVI to VGA. Still, the same problem. Definitely the video card.
Except now I'm not so sure. I just fired it up again and opened the web browser, only to have the whole computer freeze up on me (I could move the mouse, but that was all. Clicking and keyboard commands were completely useless) and then my display went dead black, without even the warning about power saving mode. The computer appeared to still be running, though. The lights were on, and I could hear fan noise. So, I powered down, waited 5, then powered back on and attempted to login as Admin in Safe Mode. Windows didn't even finish booting this time before it froze. There was also a long, continuous beep coming from within the case. The screen went dead again, the beep continued, and the computer still seemed to be running. I powered down, waited another 5, then powered back on one last time. This time, though, the screen wouldn't come on at all. The computer, though, did again seem to be running (lights, fan noise, etc). If not for the freezing and the long beep, I'd still suspect the video card, but now I'm not so sure. Does anyone have any ideas or suggestions?