ok so i just built a new computer and everything seems to be in order. i had a friend of mine check it over to be sure. when i turn the computer on, there are no error beeps and it appears to be ok. Then the screen sometimes says insert system disk but usually it just turns itself off and then back on about 10 seconds later? I have 5 fans that are all wworking so i doubt it's the cooling that causes the restart. could it be my power supply? thanks