So, after I got the power cord plugged into the back of the PSU and then plugged the other end into the wall socket (a live wall socket no less), I pushed the power-on button on the front panel of the computer and absolutely nothing happens. No lights, no sounds, no nothing. I had pulled the side cover off so I could look inside as I tried to power it up. This thing is just as quiet and dark as a tomb.
I did make sure he didn't accidentally switch the voltage on the back of the power supply. All connections look good as far as I can tell (no obvious loose wiring or dangling connections that should be plugged in).
One thing to note, when I plug the PSU into the wall outlet there is a green light on the back of the PSU that begins flashing.
I did scold him for never, ever opening up his computer and cleaning out the dust. When I did it this afternoon it was the most unbelievable sight. Everything was caked. I cleaned it out really well. All fans; PSU, case, and CPU, seem to spin fine without any difficulty.
So, bad PSU? Bad power-on switch?
Ideas, thoughts, revelations, instructions are greatly appreciated.