486 update: I thought I killed it, so I ordered a new one. Then I remembered I had disconnected something internally. D'oh!
On the plus side, there are new, modern AT PSUs available today! Hopefully it's well made. This Gateway uses an Astec. I looks solid, but will be a complete PITA to re-cap since it looks like all the leads were soldered with the PSU in the metal case. Plus... it stinks and will be a pain to clean.