Dell OptiPlex 7070 Service Manual page 55

3. To release the PSU:
a. Disconnect the CPU power cable from the system board [1].
b. Unroute the power cables from the retention clips on the chassis [2].
4. To remove the PSU:
a. Remove the 3 screws that secure the PSU to the system [1].
b. Disconnect the system power cable from the connector on the system board [2].
c. Lift the cables away from the system [3].
d. Press the blue release tab [4] at the rear end of the PSU unit, slide the PSU and lift it away from the system [5].
Removing and installing components 55