daryll1 0 Light Poster

Ok so heres the problem, my girlfriends laptop (toshiba satellite L100-170) will not start, it's very tempermental sometimes it will and sometimes it won't. If it was a PC I would go straight for a short on the motherboard but I'm not sure will be that :/
If you take the battery out and put it back in the fans will come on but when you hit the power button still nothing happens.
If any of you guys have any ideas where to start that would be great

Thanks
Daryll