i have pentium 4, 3.0gig chip,120 gig drive,128mb radeon video,1 gig ram and 400 w power supply.my previous power supply was 500w which stuffed up.my pc turns off completely in the middle of use ever since my power supply went.could it have caused other problems or do i need a 500w power supply again.i also have a dvd rom and dvd burner attached.