Power problems

[Liriel]

Today my hydro company turned my power off for 1 minute to install a smart meter. After the power came back on my computer would not start. Absolutely no power at all. I had been using a power bar but other things on the same power bar were fine. I bought a new power supply and installed it and now I have power but just to the power supply and nothing else. When I first start it up everything lights up and the fan on my cpu and the extra fan in the case run for about 2 seconds. Then it all shuts down and the only thing running is the fan on the power supply. Anyone know what the problem might be? Any suggestions would be appreciated.

 

[Tmagic650]

...and the computer was running when the power was turned off? Any add-on cards installed like modem or USB device?