Dell OptiPlex 9010 All In One (Mid 2012) - Manual (Page 24)

4. Remove the screws that secure the power-supply fan to it's chassis and lift it away from the computer.
Installing the Power-Supply Fan
1. Place the power-supply fan on the computer and tighten the screws to secure it to it's chassis.
2. Align and place the fan bracket on from the computer.
3. Tighten the screw to secure the fan bracket to the chassis.
4. Install:
a) system-board shield
b) VESA mount bracket
c) back cover
d) VESA stand
5. Follow the procedures in After Working Inside Your Computer .
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