Desktop Will Not Start After Moving?

I have a desktop computer. It has a phenom x6 1045t, 4 gigs of ram, an hd 6870, and a 530 watt psu, running windows 7. A month ago, it was running perfectly here in my dorm room. I went on winter break and drove it home with me. It was running perfectly there, too. I have just come back to school from winter break and I cannot get it to start properly. Literally NOTHING has changed with the hardware since about 4 months ago, when I first upgraded my video card to the 6870. It is plugged into the same surge protector in the same outlet it was a month ago, when it was last here. Here's what happens when I try to start it: It goes through the initial ASUS booting screen, then onto the starting windows screen. Then, out of nowhere, my monitor says it's "going to sleep," the lights on my keyboard flash, and it restarts the booting cycle. However, if I tell it to boot into safe mode, it starts without any issues. I need some help identifying the problem here. My first thought was a power issue, but again, it worked fine a few days ago, and it was working fine in these outlets before. I was very gentle in the move, so i doubt the PSU was damaged. The fans are all spinning and the LEDs still come on. Hard drive must be fine, otherwise it wouldn't work in safe mode. Ran a memory test, RAM is fine too.

Additional info: Actually, it successfully started yesterday too, in my dorm room. I used it for about half an hour then let it hibernate, and only now am I having issues. Also, the fan on my video card was going crazy, but after I re-seated it, it calmed down. I rechecked all the wiring as well and everything seems fine.