Chosen Solution
This laptop was disassembled to repair bad hinges. When it was reassembled it would not start. Memory has been checked. Backup battery has been changed. Optical and Hard drive checked. Num lock key works. On and Off button works. Screen lights to black but will not show Toshiba or launch Windows. Motherboard was changed with guaranteed replacement.
Bob, connect an external monitor and see if that shows anything. Sounds like either not all connections were seated or a bum LCD
Check the RAMs properly fixed to the slot it it is ok connect your laptop to extranal monitor if graphics comes fault occuring from your display connecotr or wires which transfer data to lcd.if both not works can assume your power management module not functioning properly. find the local place which facilatate BGA reworking and change the PM Chip
