Micro, that's awful! I have sciatica so I have some idea of chronic pain but I'm guessing it's nothing like discs actually rubbing on nerves. Stay off it, man, other than going to the doc's that is. Try lying flat on the floor. STOP trying to do stuff. Get some serious pain killers, this is what they're for.
Leave the video card, it'll keep until you've at least moderated enough to welcome a distraction. Doesn't sound like you're there.
WHEN you're better: Yes, I agree it's probably 2D-clocking. There's no solution that I know of to address the periodic drops we all get with the newer cards, but it shouldn't be booting up there. Start with no overclocking would be an obvious thing. Second would be the 301.42 drivers the nvidia site will try to push on you will probably be ok, but the ones working on this machine which houses my 550ti are 280.26. I have no reason to change, well enough alone and all that. Also can't comment on Win 7 for the same reason.
Here's something you can try when you've absolutely had enough though: try FAHv7 and let it do what it wants to default to during the install, might actually fix it. I prefer v6 so I'm not putting v7 on any more machines at this time but I sure would if it solved the problem you're having. Try the other stuff first though. Or hey, maybe try it first and maybe you won't mind it, others certainly like it. Either way I'll e-mail you the 280.26 drivers because they can be a pain to find. Oh yeah, whatever you're doing don't forget to consider running Driver Sweeper.
I'm serious, man, stop aggravating things, everything will wait. I believe I speak for Sun when I out and out warn you, I WILL bring Mrs. M. into this.
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