Toshiba Satellite L300D

Hi all.

Not posted in a while but need some help with this.

A work mate of mine ask me to help with this laptop. She said she was using it when it came up with configuration then shut itself down.
Now when you press the power button the battery and charge light comes on but the screen is blank. I can hear the cpu fan spinning but there is hard drive activate and not HD light on the front.

Try changing out the HD and tested the ram and also tried plugging to external monitor but still nothing.

Can anyone help with this as I don't have a clue as to what else to check.