Hello
I want to test a power supply unit provided to me (not new, along with its power cord), but currently do not have a PC available to do so. How can I test whether the PSU is working OK before actually connecting it to the PC?

Cheers

You need a number of tools for this, including a harness that will provide a load similar to what the system would generate. In addition, you need diagnostic tools such as a volt-ohm-ampmeter and possibly a scope. Not a job for the inexperienced or the ill-prepared.

Ultra puts out a power supply tester. It tests 20/24 Motherboard connector;Molex+12v/5v,EPS +12v;Floppy+12v/5v;PCI-E+12v;SATA+12v/+5v/ with led and sound indicators.

commented: Thanks for the lead. +13

Thanks cis7850 for the lead. It sounds like this is a dedicated device that would do what I suggested "in the raw". :-) Ain't tech great? To quote some wag or other, "Never do yourself what someone has already built and sells at Best Buy."!

A friend told me to bridge a paperclip between the green and gray wires in the 24-pin socket of the PSU then switch on, thou I've not tried it yet. Anyone can confirm if this is a good alternative as well, or it may burn the whole thing?

Do you smell that crispy odor and hear sizzling? That's your power supply getting toasted... :-) It should trip a breaker or fuse, but don't depend on that!