Only the later revisions dimmed the LED. The earlier versions turned it off instead. In this case, it's starting up but crashing before it's turned on the power LED. If he had no 5V, he would have no display at all and the Caps Lock light wouldn't work.
It's a CPU problem. probably a bad connection stopping the CPU connecting to the motherboard, so it's waiting for the chipset to acknowledge, and it's never happening so it's stuck waiting all the time.
