Hi and here it is in a nut shell. Desktop PC fan always comes on with the normal quick push of the power switch but sometimes the mobo doesn't. When it happens I'll hold the swith in till the fan goes off and then try to fire it up again but not so fast on the button this time. I hold the button in for a sec or two till I see led's lighting up so I know the mobo is booting and all is fine.
Thus the question: Is it in the switch or the psu? Any ideas? Whatever it is, it's gotten a little more freaquant but I've never had a psu only power the fan unless the button is held in longer. I built it over 5 years ago for the folks but they only used it maybe 10 times so they gave it back to me 2 months ago. So it's very low use for its age.