After a wonderful fiasco trying to figure out what caused the bluescreens in my PC, it turned out that it was a bad stick of ram. I figured I'll just get two brand new 4 GB kits - all together 8 GB, stretched over 4x2GB sticks.
All seemed well; boot screen, POST, even the GRUB bootloader (that's the term for it right...?) showed up. I selected Windows 7, and it started up seemingly fine - showed the startup screens for that - the loading and welcome screen, then my desktop. About 20-30 minutes of waiting, it would not show my icons - I could move my mouse, but the icons did not show up. At all. It would not respond either. Only one monitor seemed to actually turn on.
After about 20 more minutes of waiting I shut down - held the power button down, and shut it down. And at that point, I tried re-starting the PC - after all, that usually did the trick every single time before that.
I forgot what it said exactly, but I think it's a problem many people have with GRUB. "No boot"? Or something like that. Showed up in the top left corner of the screen and that was it. After a while of nothing happening I shut down again, and restart. Now it only shows a blinking cursor and that's it. Nothing else.
I continued testing to see if I knocked out any wires or whatever and nothing was out of place or looked damaged at all. Dusted out the PC... still nothing.
I did some googling and figured I'll have to reinstall grub or something - after loading up a live cd, I still cannot seem to even FIND the hard drives, nor can I even do the first step of most tutorials "sudo grub". It won't work. Needless to say, even after several more hours of trying to find SOME kind of problem like this, I'm stuck.
I tried replacing the old sticks of ram (even while my PC bluescreened, it still would work as long as I didn't do too much!) but it still gives the black screen with the blinking cursor.
At this point, I figured I'd be re-installing windows again but... I REALLY want to back up the HDD before doing anything.
Computer specs, if it's worth anything for this question:
Mobo: MSI 785GM-P45 CPU: AMD Phenom II x2 555 Black Video Card: I... actually don't remember that one and I don't have the box/can't find info on the card itself right now. RAM: 4x2GB PC3-8500U Crucial (Old Ram), 4x2GB DDR3-1333 Micro Center brand (Manufactured by Adata) There's also a USB card added. CD/DVD read/write drive.
EDIT (26 Minutes Later...): Well... I... don't quite know. Upon attempting to do David Schwartz advice, I proceeded to start going to the boot select, and suddenly BAM - the hard drives appeared! I selected the HDD, and GRUB just popped right up as if nothing happened! Windows is starting up as I type this.
I wouldn't quite close the issue yet; with my luck, I'll shut down the PC and the problem returns. I'll give an update if it seems that anything bad happened. But as of now, the desktop is now showing up fine, and all the cions are there. Everything seems to be working perfectly fine. I'll still run some tests to make sure everything is alright though. That's the last thing I need; to suddenly have more problems.
Eh. At least I'll be building a new PC soon.