Laptop Randomly Stopped Working

[Smausage]

I'm not 100% sure on what happened to the laptop I have... It just kinda... stopped working.

When I go to turn it on, it'll do everything it's supposed to, the lights on the keyboard turned on, and the fan would start, but then after 2-3 seconds it just stops.

It is (I think) fairly old, it's an HP 635. I can't think of anything that happened that would make it stop working, it's just been sitting on a table for a week or so...

 

[grmnlxndr]

Unplug the laptop, take the battery out and press the power button for 30 seconds (it should discharge all capacitors). Then try again.
Also try reseating the RAM dimms, then placing only one of them, checking both slots (assuming it has 2 slots).
If that doesn't work, it could be the motherborard and you need to do reballing or replace

Regards