I came home from work, to find my hard drive activity light off, which was the first sign that something was wrong, since I had left it running HDD tasks. As soon as I put away my groceries, I ran over to the computer and turned on the monitor:
Freshly rebooted desktop. Checking the event viewer told me nothing, the events listed in it were all from the day before.
So, I decided to see what BIOS version I was using and to update it to the latest stable BIOS. Turns out I was using 0202, which is pretty old, and I ran to the Asus website and found that there are two current BIOS'es: 0307 and 0402. The 0402 BIOS is Beta, unfortunately, so ultimately I opted for 0307.
Before I flashed it, I ran a diagnostic on the motherboard, and found that it was reporting the voltages to be really low. Somewhere around 8-10% lower than what the lines were specced at. So I ran the windows BIOS updater program and updated to 0307, then rebooted.
BIOS complained about broken checksum, which was to be expected, since the new BIOS reset all my settings. So I spent another 15 minutes tweaking the BIOS settings to my liking, and I disabled Legacy USB support too, since I don't plan on running in DOS mode anytime soon (or ever).
Now that I was done with that, I saved the settings, and rebooted again... and... and...
Blue Screen of Death. DAMNIT!
I figured the new BIOS must have invalidated some of the motherboard drivers, so I'll probably have to reinstall the OS; no big deal, it's a new system anyways. But first, I'll try rebooting into safe mode.
At that point I discovered that my F8 key didn't work, and it took me a few minutes to realise that (duh) I disabled Legacy USB, so of course the DOS-mode pre-winXP loader keyboard commands wouldn't work.
Okay, so now I try going into safe mode, and I still get a BSOD. Yep, time to reinstall windows. I plugged my WinXP disc into my top CD-ROM drive and rebooted again, only to BSOD again. I had forgotten that I wired both of my DVD-RW drives up to the IDE controller card the previous night, which I can't boot from. So, I powered down, and rewired the disk drives so that the top DVD-RW is connected to the motherboard and is in the boot sequence, the bottom DVD-RW is wired to one channel of the IDE controller card, and my two IDE hard drives are on the other channel of the IDE controller card.
Reboot, and I'm expecting a BSOD again, but for some reason, it boots right into Windows with no problem now, though loading takes a long time to complete, as it's apparently re-installing every device on the system (I think the BIOS replaced the ACPI interface, which required a fresh driver install). My mouse and keyboard didn't work until it was done loading (apparently it reinstalled those drivers last), and finally, they start working again for a moment... then...
I almost yelled at this point. Quickly rebooted again, went into windows with the intention of reinstalling all my drivers again just in case, but nothing happened.
Then, nothing continued to happen. The system appeared to be working. I was cautious, and started running some useless utility tasks, just to keep the system doing something, but nothing critical.
Since I hadn't exercised in two days (my first two-day exercise break in over 2 months), I decided to get my fat ass exercising for half an hour while the computer did its thing, and when I got back to it, it was still running.
So far so good. I decided now I'd like to do a real stress test, and loaded up Half Life 2, and turned all settings onto full. Not only did it work, but it looked great, and ran extremely smoothly, and I played it for two full hours, without a single problem.
Seeing as how the hour was getting late, and I had work in the morning, I exited the game and left the computer running overnight, and much to my delight, it was still running fine in the morning.
So, I guess this means that the BIOS must have fixed it. I'm crossing my fingers for now, however.