Try this first. Unplug the computer, hold the power button for a couple seconds, then plug it back in and try to start it.
If it does not start, check the power light and the four diagnostic lights on the back of the computer for indications of hardware/POST issues.
I had a short power outage will the computer was plugged into a power surge protector. Eveything else came back on except my tower, can someone help?
I am using Window XP

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