What would happen if you managed to plug a floppy drive power connector into the jumper prongs on a hard drive, and then proceeded to boot the PC?
I told this newbie at work to install a PSU into a machine that was able to POST and boot fine, until he did what he did with the PSU. Now the PC doesn’t POST at all.
On a related note, the original problem with the PC was that the customer’s digital cameras weren’t being recognized on the PC whenever they were plugged into any of the USB ports – any other USB devices were instantly recognized, however.