Laptop won't boot

[Ender]

I have an HP Pavilion dv2000 laptop with me and it won't boot up. I hook it up to the charger and press the power button and it's completely unresponsive. I've tried holding the power button down but it still won't boot.

Does anyone know what could be wrong with it, or how to go about figuring out the problem? I was thinking that probably the battery is dead. Is this the only thing that can be causing it? I would hate to buy a new battery and then discover that the battery wasn't the problem.

[deadly7]

Do any lights / the heatsink fan turn on? Sounds like a fried mobo.

[Ender]

I think the only light that turned on was the light indicating the charger was in. I forget, though, since it was my friend's computer and he already took it back with him.

[iago]

A working laptop that's plugged in should boot with a dead battery (or even without a battery). Make sure your charger's working, though.