Power adapter plugged into the wall socket, green LED on power adapter lights up.  Soon as you plug the power into the motherboard the LED on the power adapter goes off.  This is a safety feature built into the power adapter for protecting the itself from getting zapped by turning itself off.  The only way to get the power adapter working again is to remove it from the motherboard and from the wall socket.  Some of the power adapter will try to restart itself but if you don’t disconnect it from the motherboard the power adapter will just goes in a loop of restarting.  In that case the LED on the power adapter will blink on and off.

Note: This may not work the way it should be if you are using after market or universal AC adapter.

Tested MOSFETs near power in section and found one of the MOSFET to be shorted.