Windows 7 does not boot (at all)

I'm not sure why you got no RAM errors when you retested since you had a lot of them at first. I'd do it over following the steps carefully in Jonathan's tutorial.

Do the problems go away if you use a tested-good RAM stick in a known-good slot? If so replace the bad stick or avoid the bad slot, whichever is indicated by testing.

If this again prove fruitless then try wiping the HD of all code with Diskpart Clean Command since bad boot code could cause these problems in both OS's. DISKPART At PC Startup

Then use the latest official installer and follow these same steps to get a perfect Clean Reinstall - Factory OEM Windows 7

gregrocker: i did test them individually in all the slots (one by one).

my desktop seems to be ok now...
so here's what i did:

i wiped the entire hard drive, including the previous vista factory restore partition. i did a clean install of windows 7 (via DVD). everything seemed to go ok, until it rebooted without warning. it didn't have any problems loading up windows again, though. so far i haven't had any problems loading windows during startup.

HERE'S THE FUNNY THING!
the outlet my computer was connected to has a tendency to flicker on and off. has some faulty wiring or something. i deduced that this flickering caused the pc to reboot, so i got an extension cord and plugged the pc into another outlet.

so far, no sudden reboots.

i've checked my event viewer and there's all sorts of errors that i still have to sort through (none of them too critical that would affect system performance, i hope). i still need to reinstall drivers, so i'll see how things will end up.

this is just ridiculous. but at least i have my OS startup problems solved. thanks for all the help, ztruker, greg.

If it was the bad wall a/c outlet then you're lucky it didn't damage the mobo with it's power fluctuations. I'd also have it looked at as it could be a fire hazard.

gregrocker said:

If it was the bad wall a/c outlet then you're lucky it didn't damage the mobo with it's power fluctuations. I'd also have it looked at as it could be a fire hazard.

Yes, it's not something I would ignore. Not using it because of the problem doesn't cut it either; it can be a hazard even if you're not using it.