PC won't turn on after probable power surge through USB port

[harpsm1]

I suspect I triggered a power surge through my Asus Aspire's on-board USB port by plugging a cable into it that was also plugged into a wall charger via a y-cable. The moment I did this, my PC turned off and pressing the power button would not turn it back on again. I unplugged everything from the USB ports and unplugged the computer power cord. When I plugged the power cord in again, I heard a mechanical initialization sound (the same sound I hear every time I start up the computer - probably the DVD drive?) and the processor fan started running at full speed, which is unusual. Pressing the power button has no effect at all. Since there is power going to at least some components, I suspect I fried the processor or something else on the motherboard.

Does anyone have any advice on where I should start in trying to diagnose and fix the problem? I don't want to start replacing things unless I have a sense of the problem first.

 

[RememberThe5th]

I would unplug PC from wall, switch PSU ON (while unplugged), remove shiny battery from motherboard, hold power button for 30s~, remove front USB ports from motherboard, track the cables that lead to usb's and disconnect everything that is going from usb to motherboard, stick battery back into motherboard, switch psu off then plug it in wall and switch psu on and try to power up.

Oh and don't disconnect the power button!

 

[harpsm1]

I would unplug PC from wall, switch PSU ON (while unplugged), remove shiny battery from motherboard, hold power button for 30s~, remove front USB ports from motherboard, track the cables that lead to usb's and disconnect everything that is going from usb to motherboard, stick battery back into motherboard, switch psu off then plug it in wall and switch psu on and try to power up.

Oh and don't disconnect the power button!

Well, after waiting 12 hours since the problem started, my computer now starts back up normally, at least superficially as if nothing ever happened. Given that the fan was running full power when nothing else would turn on, I wonder if the power surge caused an overheat, and some logic on the board would not allow the system to turn on for a while to allow for cooling (I'm far from an expert, so that's just a wild guess). I'm still not sure that there are no lingering issues (my Internet connection worked the first time I got the computer back on, but then didn't work the next time I turned it on, which may or may not be a coincidence), so I will keep Robert Ban's great advice in mind if something is amiss.

 

[RememberThe5th]

Seems like the electricity discharged.
Well happy gaming then

 

[harpsm1]

Seems like the electricity discharged.
Well happy gaming then

Thanks! Though I am definitely NOT gaming on this dinky little Acer Aspire!