New PC won't boot after Windows Update

[Slater]

So, no more than a week ago, I got a new PC.

Everything was magical and wonderful. It has a 128GB SS Drive and two 1TB secondary drives. 12 GB of RAM and two NVidia GeForce GTX460s in SLI mode. 3.06 quad-core i7 processor. Everything was soooo smooth. No problems, no errors, no beeps or buzzes. Quiet fans, low temperatures.

Last night, I got home from work, fired the PC up as usual, played a little bit of Doom3 and Audiosurf because I've been too busy lately to install anything that's not already in my steam account. Even did a full-system virus scan (CA Antivirus) and was pleased to see a clean system. Well, before I knew it, it was 11 PM and I was feeling pretty tired. Windows 7 said it wanted to install an OS update. I thought to myself "That's cool, I've done that only a thousand times in the past." So I let it install the update and shut down. Usually, these kinds of updates don't perform the final steps til you start the system up next, so I figure that's what it had planned.

Got home from work today and decided to fire it up for the long weekend. Before, it loaded Windows to the login screen in about 45 seconds. So, something seemed very off when 3 minutes later, there was still a blinking DOS-esque text cursor on the screen. That's odd. What could take so long? Well, 3 minutes turned into 10, and then 20. I restarted the system. BIOS flash by in a few seconds, no errors or beeps or red lights or anything. And then more black screen with blinking cursor.

At this point I'm very worried. I reboot again and peek around in the BIOS. Everything looks fine. Temperatures are great, RAM looks ok. All drives accounted for. But it just won't boot past the BIOS.

Popped the system restore disk in; ran it with no errors. Rebooted and no luck.

Right now it's just sitting there with the black screen. I'm at a loss for what to do next. Any suggestions?

EDIT: Update, I seem to have possibly fixed it. Somehow, something was a little wonky in my boot location priorities. How this randomly happened, I have no clue, but at least now I'm getting to Windows.