PC Perpetual Restart

Hello all, I'm extremely new to forums and the like, so I'll do my best to work with whomever wishes to assist me toward getting my issue fixed.

I run an Alienware X51 R2 with factory set hardware and Windows 8 OS. I upgraded to Windows 10 a while ago (huge mistake) and decided to revert back to Windows 8.1. I went through the steps provided by Microsoft to return my PC back to Windows 8.1 and all seemed to go accordingly. This was, until my PC began to perpetually restart over and over and over again, to the point where I cannot even reach a screen that allows me to boot the system up in any other way.

Upon starting up my PC, it will go through the regular process with the little blue loading bar and the options to press F2 or F12 for Setup and Boot Options, respectively. Then, the series of little dots will rotate on my screen, showing that it's continuing to load the OS. But, instead of properly loading the OS, all I get is a split-second of a blue screen with a frownie face saying "Your PC ran into a problem. We're just collecting some error info, and then we'll restart for you. (O%)". Normally, what happens next is that the 0% works toward 100% and I sign into my Microsoft account; but instead, my system just reboots infinitely, without any progress ever being made. I figure something's corrupted. Is this even repairable?