Hi, I have a difficult one here. When I connect power cable fan spins for around 5 sec then turns off (power button flashes 3 times that means that power cable is connected). If I press power button, button led flashes, fan spins but no image on screen.

What I have tried:

-Laptop has on board ram so I tried installing external ram

-I have monitored voltages, 5v and 3v3 volts are present. As soon as the system starts up, these voltages go up, then they go to 0.(main 19 volts is still present).

-I have also tried resetting bios and flashing bios

-thinkengine chip (super IO) seems to work fine

Did i miss something? I can provide shematics if needed.