This only relates to Power switch HD and Power Leds.

Front USB is unknown.

                       O   O
                       O   O
                       O   O
                       O   O
                       O   O
                       O   O
                       O   O
                       O   O
                       O   O
      PWR + -- O   O -- PWR GRD

 HD LED + -- O   KEY
                       O   O -- PWR LED -
                       O   O --GRD
                       O   O -- PWR LED +
                       O   O --PWR LED GRD
                       O   O
                       O   O