Check the startup resistors on the PSU -- desolder any melted/weird looking resistor and measure them. Also check for bad solder joints, especially on the coils.

on't rely on in-circut measuring of components, it's never a good idea. Oh, and don't replace the PSU caps with mid/hi-ESR ones, it'll stress the PSU and make it unstable. Low ESR is the way to go in switching power supplies.

Gotta save that poor PSU while you can. Now it's :disapprove: but it might turn into } if you don't help him!