Dell OptiPlex 990 (Early 2011) - Manual (Page 47)

Control Panel
18
Removing the Control Panel
1. Follow the procedures in Before Working Inside Your Computer .
2. Remove the cover .
3. Remove the front bezel .
4. Remove the drive cage .
5. Remove the memory .
6. Disconnect the control panel cable from the system board.
7. Unthread the control panel-speaker cable from the chassis clip.
8. Remove the screw that secures the control panel board.
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