Laptop power-on problem. Any ideas?

I have a Dell Latitude CPx and it when I press the power button the
green light comes on for a minute, then goes right back off. Same thing
when it's docked to the docking station and I press the docking
station's power button.

At one time it was doing this but I could still get it to boot up on
occassion, but now it just won't boot up at all, turns on, then right
back off. What could be causing this?


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maxsideburn