depending on how old the computer is i'd think. I'm not entirely familiar with all the tools but in most cases the beep codes should be able to tell you something.
however many people stated that in the video, they heard no beep codes or whatever.
the only things that would keep a computer from booting to POST would be the ram, the motherboard, and the processor.
again, I don't have any kind of special diagnostic tools other than extra parts to swap in and out. Not sure what you'd do to diagnose it otherwise.
what struck me as particularly dumb were the people who said it was the hard drive, or said "this AND that" (picking 2 of the 3 POST failing parts)
oh yeah, and the people who said "video card"
