I built a system with an asus p8b75m le plus board, 8gb of ram and an i5 2320 as a spare parts build with one of my old gpus. Now, its starting to power on and off and I'm worried this may kill the computer, it isn't the motherboard, ram or cpu as those are brand new. Could it be my power supply? Its an hp 300watt power supply as well, could this be the cause of failure? I have like a few other power supplys to test this with, what do you think?