I've recently encountered an odd problem with my computer.
About a month ago, my screen randomly would blink off for about 3 seconds, then on for 3. Slow response times when the screen was blinking on, none when it was off. After dealing with this issue for about a week, I am unable to boot into Windows (running XP Home), getting stuck (but not having the screen blinking) at the loading screen with the scrolling load bar. Safe mode works without issues seemingly indefinitely, however.
At this point, I elect for a reformat/reinstall. Doing so did not fix the problem, but rather after a few more reboots, make it so that the machine would no longer POST, hanging at the video card check the BIOS does.
After a little thinking/troubleshooting, I was able to figure out that the problem seemed to lie with the power supply. I have no way of checking the graphics card or motherboard, but replacing the power supply seemed to fix the problem.
Now, I am encountering the same issue again with a power supply about a month old. I went with a 650 watt PSU, "Antec TRUEPOWER TRIO". No other configuration settings have changed. The issue came on slowly, gradually worsening to the point where I am now once again unable to boot into Windows, though safe mode is perfectly fine and stable (which I really don't understand if it's a base hardware issue).
I am at the point where I would be happy to pay for decisive assistance in the matter, but otherwise would welcome any advice.
My current leanings are towards replacing the PSU again (as it's under warranty), then looking toward mobo/video card. What I just don't understand though, is how hardware could be perfectly stable in safe mode, but utterly fallable in a fresh install of windows, which makes me really want a software solution.
Other info: Temperature sensors report around 42C for both video card and CPU, 34C ambient case temp. Before boot failure, problem only seemed to occur with a web browser open (regardless of whether Opera, Firefox, or IE7 was used). System is spyware and virus free, negative results with adaware, spybot, and a current version of mcafee.
My other specs:
Athlon X2 3800+
2 GB Corsair RAM
300 GB SATA HD
Creative Audigy 2 ZS (PCI)
Evga Geforce 7600 GT (PCI-E 16x)
GIGABYTE GA-K8N Pro-SLI Socket 939 NVIDIA nForce4 SLI ATX AMD Motherboard