MB or Power Problem with E-Machine

Have a W3615 with D945GClG1 MB. Trying to determine if MB or switch is faulty. Have replaced faulty PS. Anyone knowledgeable or have one of these systems or MB in another unit, please advise of pin order and exactly how the connections are made to the pins from the power switch, power led and hdd led. Have seen diagrams of MB without actual connections but since mine is still not working, just want to verify before replacing. Thanks.

I test a suspect case power switch by swapping the case power and reset switches, then use the reset switch to turn on the computer. You can also momentarily short the green wire to one of the neighboring black wires with a paperclip - carefully, carefully.