How do you come to that conclusion?
The first thing you should do: if the motherboard does not turn on, is to verify in which ACPI state the motherboard is, for this it is necessary to review the schematic in the section on ignition blocks.
Then you must check the inductors, that none is marking zero when you measure resistance to Ground, if it marks zero on the diode scale, measure again on the Ohm scale and post the values.
Good luck!