A motherboard failure on a laptop that is out of warranty would usually mean that its time for a new laptop. The price of a new motherboard is usually higher than the current value of the laptop.
Symptoms:
Plug in the power adaptor and try to start the laptop.
- Nothing happens.
- The ON light comes on, the fan spins, but nothing on the screen [black] and you cant hear the HD working after 10-15 sec.
- The ON light comes on, the fan spins, but after a few seconds the light goes off.
- After pressing the ON button the screen stays black and you can hear a quiet high-pitched sound coming from the laptop.
Troubleshooting:
Look for the lid closed switch and try pushing it a few times. Its usually a small switch near the hinges that is pressed when the lid[the screen] is closed. Sometimes these switches get stuck in the lid closed position that results in black screen[no backlight] or non-starting laptop. Also some laptops have a magnetic switch [newer Dells and most Apples], that doesnt get stuck.
Test the laptop with another power adaptor. Although not common, the adaptor can fail and not supply the needed voltage even if it has a green power on light that lights up when you plug it in. Even if you measure the output voltage and its OK, the adaptor may have failed and wouldnt supply that voltage under load [typically 3.5A to 6A]. You can use an universal adaptor or go to an independent repair shop and ask them to check it [some shops will try to charge you for estimate for doing just that, so ask in advance].
Reset the RAM. See the article on RAM failures for instructions.
Remove the hard drive and the CD/DVD if its easily removable.
Finally try to start the laptop again with only the power adaptor plugged in and with the RAM reset and all removable components and the battery out. If theres still nothing on the screen, you will need to bring it to a repair shop.