Dell OptiPlex 990 (Early 2011) - Manual (Page 33)

Chassis Fan
12
Removing the System Fan
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. Disconnect the system-fan cable from the system board.
6. Disengage the system-fan cable from the chassis.
7. Remove the screws that secure the fan to the chassis.
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