Dell OptiPlex 9020 All In One (Mid 2013) - Manual (Page 12)

4. Lift the cover and remove it from the computer using the notches near the input/output (I/O) panel.
Installing the Back Cover
1. Align the back cover to its original position on the computer and press until it clicks in place.
2. Tighten the screws to secure the back cover to the computer.
3. Install the VESA stand.
4. Follow the procedures in After Working Inside Your Computer .
Removing the Memory
1. Follow the procedures in Before Working Inside Your Computer .
2. Remove the:
a) VESA stand
b) back cover
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