If you don't know how or have never used a digital volt meter for such purposes, and have some reason to believe it is suspect, go get help or another power supply.
Except for the motherboard, you could check the other outputs using an old device like a floppy or fan with those connectors, but be careful.
They are generally cheaper to replace.
What is the easiest way of testing the power supply WITHOUT plugging it into all the devices at the computer? I have heard that if defect, it may fry the mobo so here I am with a PSU in my hand waiting for somebody to tell me how to test it without putting it back in...
Thanks in advance.

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