Dell OptiPlex 9020 All In One (Mid 2013) - Manual (Page 11)

5. Remove the screws that secure the VESA stand to the computer and lift the VESA stand away from the computer.
Installing the VESA Stand
1. Align and place the VESA stand on the back of the computer.
2. Tighten the screws that secure the VESA stand to the computer.
3. Place and press the VESA cover on the computer, until it clicks into place.
4. Follow the procedures in After Working Inside Your Computer .
Removing the Back Cover
1. Follow the procedures in Before Working Inside Your Computer .
2. Remove the VESA stand.
3. Remove the screws from the base of the computer.
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