So, in the end, the problems DO seem to have been software-related, because a fresh install made everything work fine. A couple of quick bits of software install and it's ready to go for Erik. Just gotta move the desk up to his room, and once he's home, we'll have him clean off his old desk and figure out what we'll do with it.

Speaking of cleaning, geez, the amount of dust, cat fur, and little bits of junk behind that thing was scary...