Dell OptiPlex 390 (Mid 2011) - Manual (Page 34)

8. Slide the power-switch cable out through the front of the computer.
Installing The Power Switch Cable
1. Slide the power switch cable in through the front of the computer.
2. Secure the power switch cable to the chassis.
3. Thread the power switch cable into the chassis clip.
4. Connect the power switch cable to the system board.
5. Install the
drive cage .
6. Install the front bezel .
7. Install the cover .
8. Follow the procedures in After Working Inside Your Computer .
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