No boot up, screen lights up, windows 7

[jefb]

I have a Toshiba Satellite laptop running Win 7. When I power on, the lights to show ac power light up. The back light on screen is visible but NO BOOT. Laptop does nothing. Fan works. Battery works
ac cord works. Where do I begin to troubleshoot?

 

[xtreme5]

remove all the ram sticks for a while then put them back also check individually if problem not solve?

 

[jefb]

I will give that a try

 

[jefb]

Didnt work. Still nothing. So I tried to put in a working hard drive and ram from a same model spare. No luck.