flip the power on/off switch on the back of the PS (if you have one), push in the power switch. Reconnect the power cord and see if your power up.
I have a 2002 Gateway 300s and was trying to install software. When i tried to quit out of the instalation, the computer froze, and I had to shut it off. When i tried to restart it, nothing happened. The light came on under the power button but there were no beebs and i could not hear the drives spinning at all. I checked the power supply so i know that it is not the problem. What happened and what should i do?