In this video, we demonstrate how to remove and install the power-supply unit. Before removing the power-supply unit read through the safety guidelines to protect your computer from potential damage and ensure your personal safety.
For more information about safety guidelines see the XPS 8940 Service Manual at dell.com/support. Before you begin, turn off your computer and disconnect all attached peripherals.
Before removing the power-supply unit you first need to remove the left-side cover graphics card and 3.5 inch hard drive. To remove the left-side cover loosen the two captive screws that secure the left-side cover to the chassis.
Using the tab on the left-side cover slide and lift the left-side cover off the chassis. Now, let’s remove the graphics card. Lay the computer on the right side disconnect the power cables from the graphics card and remove them from the routing guides on the graphics card support bracket.
Pull together the securing tabs on the graphics card support bracket and rotate to remove it off the chassis. Lift the pull tab to open the PCI-e door.
Now, push and hold the securing tab on the graphics card slot and lift the graphics card from the graphics card slot. Now, let’s remove the 3.5 inch hard drive.
Disconnect the data and power cables from the hard drive. Remove the cables from the routing guides on the hard-drive assembly. Remove the screw that secures the 3.5 inch hard-drive assembly to the chassis then lift the hard-drive assembly away from the chassis.
Now, let’s remove the power-supply unit. Disconnect the power cables from the system board. And remove them from the routing guides on the chassis.
Then remove the three screws that secure the power-supply unit to the chassis. Press the securing clip and slide the power-supply unit away from the back of the chassis and lift power-supply unit off the chassis.
You’ve now successfully removed the power-supply unit. Now let’s see how to install the power-supply unit. Slide the power-supply unit into the chassis until the securing tabs snap into position.
And replace the three screws that secure the power-supply unit to the chassis. Then route the power cables through the routing guide on the chassis and connect the power cables to the respective connectors on the system board.
Once a power-supply unit is installed, install the 3.5 inch drive graphics card and left-side cover. Align the hard-drive assembly with the tabs on the chassis.
Using the alignment post, align the screw hole to the hard-drive assembly with the screw hole on the chassis. Replace the screw that secures the hard-drive assembly to the chassis.
Route the power cable and data cable through the routing guides on the hard-drive assembly and connect the cables to the hard drive. Align the graphics card with a PCI-e express card connector on the system board.
Using the alignment post, connect the card in the connector and press down firmly. Ensure that the card is firmly seated. Then close the PCI-e door.
Replace the graphics card support bracket that connects the graphics card. Route the cables through the routing guide on the graphics card support bracket and connect the power cables to the graphics card.
Once a graphics card is installed, install the left-side cover align the tabs on the left-side cover with the slots on the chassis and slide it towards the front of the computer.
Then tighten the two captive screws that secure the left-side cover to the chassis. The power-supply unit installation process is now complete.
For more information, see the Service Manual document at dell.com/support.
