Dell Inspiron 3470 Service Manual page 60

3 Disconnect the optical-drive data cable from the system board.
4 Disconnect the power-supply unit cable from the system board.
5 Disconnect the hard-drive data cable from the system board.
6 Disconnect the hard drive and optical-drive power cable from the system board.
7 Disconnect the power-button module from the system board.
8 Disconnect the processor power-cable from the system board and remove the processor power-cable from the routing guides on the
chassis.
9 Remove the six screws (#6-32xL6.35) that secure the system board to the chassis.
10 Slide and lift the system board at an angle to remove it from the chassis.
60 Removing the system board