Dell OptiPlex 9010 (Mid 2012) - Manual (Page 34)

Installing the System Board
1. Align the system board to the port connectors at the rear of the chassis and place the system board in the chassis.
2. Tighten the screws that secure the system board to the chassis.
3. Tighten the hex screw clockwise.
4. Re-connect all the cables to the system board.
5. Install the:
a. heat sink
b. expansion card
c. drive cage
d. front bezel
e. cover
6. Follow the procedures in After Working Inside Your Computer .
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