Laptop troubleshooting issues: What to do when your laptop won't display

The first thing you can do is to remove the RAM from its slot and clean it, then fix it back there carefully. 
When fixing it back, you may try another slot. Don't forget that a bad RAM can also cause your laptop to fail to display.
If you have two RAM, remove them, place only one RAM and check the display. If you fail to get any display, change the slot.
If the problem persists, try connecting an external monitor to your laptop. Just look for the VGA connector on your laptop. Connect it to the external monitor, then switch on your laptop.
If you're able to get the display on the external monitor, it means the problem may be from the backlight bulb or with the inverter.
In most cases, you can't tell whether it's the backlight bulb or the inverter board that's causing the problem. One has to change either the inverter board or the backlight bulb to know which is causing the trouble.