Dell OptiPlex 7080 Tower Service Manual page 78

Steps
1. Slide the power-supply unit into the chassis until the securing tab snaps into position.
2. Replace the three screws (#6-32) that secure the power-supply unit to the chassis.
3. Route the power cable through the routing guides on the chassis and connect the power cables to their respective connectors on the
system board.
78 Disassembly and reassembly