If your PC won't boot, there can be several causes.

One cause is if your computer is not on a Battery Backup, (UPS)
Rapid power fluctuations in this area can leave the Capacitors in your PC partially charged, "confusing" the electronic circuits, not being able to turn on your computer, or causing it to behave erradically.
Bad Capacitors, or CAP's, can be identified by bulging or leaking, or corroded tops like the picture below-

BUT

If your computer turns on, and behaves erradically, it could be a Windows Driver, or Windows Corruption issue, or a failing Hard Drive.
DON'T WAIT!!! Call for an appointment today!

540-967-1578 - Ask for Bob