Crash on Windows startup

[Myounage]

Alright, so a few weeks ago I tried testing the Nvidia Overclocking utility (system tools). The OC worked fine in that session, but when I rebooted once I saw the tray icon the screen went to...junk. Irrecognizable junk. I ended up completely abandoning that XP install and reformatted. I figured it was trying to set all the settings I didn't touch at staryup (CPU frequency, RAM timing, other crap that really just should not be in there). Oddly enough using a command-line only utility on Linux for the official nvidia driver driver worked flawlessly. That's right, a program written in spare time by a hobbyist for the second-priority driver works better than Nvidia's own.

Now, I installed Rivatuner and set it to apply my OC at startup, no problems. I was fiddling with it and today it asked me to reboot to detect default frequency (I had messed with it, and it wouldn't come down with the menu, so I went with it.) Now it's doing the same damn thing system tools did. I'm in safe mode right now disabling rivatuner's startup entires and the Nvidia performance service. Anyway, my clocks are 500/333 with a default of 400/280, and the card gets up to 70-78 C under load (ATI tool running in front of another fairly intensive 3d app. No system restore, since I've always viewed it as a crappy MS service that's dumbed down beyond its usefulness because they'd get sued if it didn't suck. What's my best course of action? I'm not reformatting again.