Laptop won't even power up.

A friend just gave me this old Asus Presario M2000.
It's been plugged into the power supply for two days,
and a voltmeter tells me that the power supply Does work.
With the laptop battery in, or the battery out,
the laptop shows No signs of any life.
No lights, no noise... nothing.

Might the problem be a bad connection on the motherboard?
Any other ideas?

Thanks, people.

Mark53