The last one of these that died on me, DrAudio helped me with. We finally chased it to an open resistor that was supposed to "tickle" the oscillator chip and get it conducting so it would switch. Applying a few volts from a battery would kick it off and then it would run but it would not self-start. The resistor looked fine but it was completely open. No idea why it happened, its the only non-original part in that power supply still. The caps were all fine.