Computer Hardware Help → Power Supply - working one day, but not the next

I was working on this one system (custom built several years back) where they said it was working the day before, and then when they tried to power it on the following day - nothing, it was dead. I pulled the PSU, jumped the wires and it was indeed completely dead.

I've never seen a PSU go without some sort of warning (smell, scorching, noise, etc.) so before I simply replace the PSU (and risk blowing out a brand new one), is there anything else I should look for?

Take it apart.... Any obvious sign of damage?

Other than dusty and cobwebs, it all looks clean. No obvious smell of burnt electronics.

if the PSU looked OK, are there any signs of damage to other components inside the case? Also, does the PSU have a fuse that might have blow or circuit breaker that might have popped?

Several years old? Power supplies die after time. Caps dry out, leak you name it. This might sound odd but one of the worst things for a PS is being turned off.
I used to repair supplies and some would run for 10+ years then you shut it down once never to work again.

Interesting. I bet that's what happened to mine.

I had the same problem like this several months ago, but i dont know why its happen, after that i just change the psu. one thing more you should check all of your power connection that within the system and ensure that no problem is there.

I put in a new supply and everything is back to normal without any other issues. Guess that old PSU couldn't take another power-on cycle.