Alright, well it's nice to know what the issue is. I guess I'm fine with that, since I've had it for about 4 years and have gamed the hell out of it!
And it was quite teasing how the computer turned on, then off. I would switch off/on the PSU switch, then it would start up, and run fine until I shut it down the final time, when it just didn't start. Ugh!
Well, I guess I'll get a new Gigabyte board, since it has served me well, and possibly get a new processor...
Thanks again so much for your help, Davcon!
I guess it was it's way of telling you it's time for an upgrade.
775 is kinda long in the tooth considering what's available these days.
That being said i strongly advise you to have the psu's voltages checked out at a reputable pc shop before you spend any money on a new platform.
Your psu is not considered very good electrically.
Voltage regulation on your unit is sub-standard according to this review.http://www.hardwareheaven.com/reviews/833/pg1/fsp-everest-80plus-800w-psu-introduction.html
It may no longer be providing the proper voltage to power your mobo and/or has subsequently damaged it.