Dell Precision 3660 Manuel De Maintenance page 52

Steps
1. Disconnect the power cables from the connectors on the system board and unroute them from the routing guides on the chassis.
2. Remove the three (M6x32) screws that secure the power-supply unit to the chassis.
3. Slide the power-supply unit away from the back of the chassis.
4. Lift the power-supply unit off the chassis.
Installing the 500W power-supply unit
Prerequisites
If you are replacing a component, remove the existing component before performing the installation procedure.
WARNING: The cables and ports on the back of the power-supply unit are color-coded to indicate the different power
wattage. Ensure that you plug in the cable to the correct port. Failure to do so may result in damaging the power-supply
unit and/or system components.
52 Retrait et installation de composants