The HDD's under the touchpad, has he unscrewed and reseated the HDD?
What won't boot? Ie: what does it 'crash' on, like the BIOS, the windows loading screen?
It crashes on the windows loading screen.
I tried to open it, taking off the RAm, HDD n keyboard n closed it back. It started but stooped at the windows loading screen as usual. Now it won't even start at all. When i press the power button,it turns on, fans spins for a few seconds n goes off. I still believe it will come up, but i need help/suggestions from u. Thanks