The brownout probably tripped the thermal breaker in the power supply. Leaving the thing unplugged a while resets it.
Why did this happen?
Breakers trip because too much current is being drawn through them. More current = more heat. A breaker trips because a component inside of it expands with heat and opens the switch. What you probably experienced was a low voltage condition known as a brownout. Mostly reactive loads (like your computer's power supply) respond to changes in the supplied line voltage by drawing more or less current to compensate. If a device requires 350 watts of power to run, it is going to attempt to draw that 350 watts regardless of the line voltage. So, if the line voltage dips too far, your PC will draw a ton of amperage in an attempt to stay running, and it will cause the thermal breaker in the power supply to trip. Your surge protector will do nothing for you here because it's not a surge, it's a sag. The only thing that can protect you from a sag is a UPS, though you would want one with good transient response (which means $$$).
Feel free to contact me if you need legal assistance. I have a great lawyer that helped me with an ex who violated my privacy and kept harassing me on MySpace and Facebook. He's very good. And there is legal precedent. - linuxpro
He is hold back the legion of boom - skater18000