Computer boots but doesn't get to login screen then restarts

rlives

Honorable
Jun 26, 2013
16
0
10,510
First off, sorry if this is in the wrong category. I figured it'd be the most fitting as I don't have a specific idea as to what's wrong.

[Here](http://youtu.be/ulY3byapz30) is a crappy video of what happens.
In the video I turn on my computer and it boots normally for about 20 seconds, then the monitor displays "No signal" then my computer reboots. This repeats until I force shutdown my computer.
My specs are:
AMD FX-6300 CPU
ASRock 960GM/U3S3 FX 760G AM3 MB
VGA Sapphire HD7870 GPU
EVGA 600W PSU
2 x 4GB GSKILL RAM
Seagate Barracuda 1TB HDD