Dell OptiPlex 790 (Early 2011) - Manual (Page 34)

8. Lift and remove the system fan out of the chassis.
Installing The System Fan
1. Place the system fan in the chassis.
2. Tighten the screws to secure the system fan to the chassis.
3. Thread the system-fan cable into the chassis clip.
4. Connect the system-fan 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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