I just recently built my desktop and I haven't installed an OS on it yet. When ever I connect the PSU plug the computer turns on and goes through a lot of error codes and turns off again. Some of the error codes I saw are ff, 36, 79 and 99 and a few more which cycles past really really quickly.
I use Asrock Extreme 4 and Fx6300
I use Asrock Extreme 4 and Fx6300