NO power fan noise

This came into place after i shorted the bored with 12 volts current, that caused not any sign of life no lights no power, ive managed to send it to repair service they said we have changed intel north bridge chip after we figured out that the short was from it then the lights went back working and the pc turn on with black screen and fan noise!

they managed to replace bios chip with no luck, can any body suggest me any profisional repair service worldwide ?