You must always, always unplug your computer during storms.
How many beeps does it make?
No Beeps -> No Power, Loose Card, or Short.
1 Short Beep-> Normal POST, computer is ok.
2 Short Beep-> Review screen for error code.
Continuous Beep-> No Power, Loose Card, or Short.
Repeating Short Beep-> No Power, Loose Card, or Short.
One Long and one Short Beep-> Motherboard issue.
One Long and Two short Beeps-> Video (Mono/CGA Display Circuitry)
One Long,Three Short Beeps.-> Video (EGA) Display Circuitry.
Three Long Beeps-> Keyboard / Keyboard card error.
One Beep, Blank Display-> Video Display Circuitry.