First up, some backstory: About two weeks ago (maybe a little more now), I decided to give the Windows 7 RC a try. I had been wanting to do a reformat for a while anyway; I like to do one about once a year even if the computer is still running good, because it always seems to make everything run better. Anyway, since the RC is out there I decided to give that a try, backed up all my important stuff, and wiped my Vista partition. I made two partitions, dividing the drive in half; one for 7, one for another Vista install should I need it. There's also a 10GB recovery partition that I never wiped out, even though I don't plan on ever making use of it, I was afraid that Vista might not install if I did (it's an OEM disc and doesn't prompt for a serial when installing; my guess is it checks for this partition's presence).
Anyway, 7 installed fine, I used it happily for about a week (I still don't see what the big deal is though; it's Vista with a few new features, which are nice features, but given how much people supposedly hated Vista...), then I started running into an issue when booting. Everything would go smoothly until the Starting Windows screen appeared, then the computer would just shut itself off. This happened very rarely, I checked for conflicts with the hardware I had plugged in, and uninstalled a few things I had installed just before it started occuring, but the issue kept happening. 7's built in startup repair supposedly fixed an issue, things went smoothly for about a day or two, then it started happening again. Not only that, it started happening much more frequently; every time I turned my computer on, and occasionally more than once. It got bad enough that I decided to reinstall Vista a few says ago, assuming there was just something about my hardware that 7 didn't like.
Installed Vista and the two service packs, everything seemed to be great, until the next day when I turned the computer on. Same exact issue. This never happened to me before installing 7, so now I've pretty much ruled out hardware incompatibility as the issue (I suppose it could still be an issue with the hardware itself and not the OS, and it's just a coincidence it started acting up shortly after installing 7). I used the recovery console on Vista to rebuild the boot record, but the boot menu was displaying fine and it only turns off after Windows starts loading, so I really don't think it's that. Does anyone have any ideas? I've certainly run out. Right now I'm running off an Ubuntu live CD because I couldn't even get Vista to boot this morning (eight attempts, it's never taken more than three, and even that's rare) and I'm considering installing just to see if this issue also affects a non-Windows OS.
Well, I installed Ubuntu and am able to boot into that just fine. I'll have to give Vista a shot later (7 isn't even displaying in the menu, maybe something really was wrong with it?).
Okay, choosing Vista from GRUB brings me to the standard Windows menu for selecting which OS to boot (which has 7 listed). I've never done an Ubuntu installation with more than one version of Windows installed, so I didn't realize this is how it would work. Anyway, everything seems fine now, I was able to boot into Vista just fine twice now. Hopefully it stays working.
