Removing the I/O board.......................................................... 53Prerequisites.....................................................................................................53Procedure.........................................................................................................53Replacing the I/O board...........................................................55Procedure.........................................................................................................55Post-requisites................................................................................................. 55Removing the heat-sink assembly......................................... 56Prerequisites.....................................................................................................56Procedure........................................................................................................ 56Replacing the heat-sink assembly......................................... 58Procedure........................................................................................................ 58Post-requisites................................................................................................. 58Removing the power-button module................................... 60Prerequisites.................................................................................................... 60Procedure........................................................................................................ 60Replacing the power-button module................................... 63Procedure........................................................................................................ 63Post-requisites................................................................................................. 63Removing the system board................................................... 64Prerequisites.................................................................................................... 64Procedure........................................................................................................ 64Replacing the system board....................................................69Procedure........................................................................................................ 69Post-requisites.................................................................................................696