Dell OptiPlex 990 (Early 2011) - Manual (Page 39)

Installing The Input/Output (I/O) Panel
1. Insert the I/O panel into the slot on the chassis front.
2. Slide the I/O panel towards the left of the computer to secure to the
chassis.
3. Tighten the screw to secure the I/O panel to the chassis.
4. Connect the I/O panel or the FlyWire cable to the system board.
5. Thread the I/O panel or the FlyWire cable into the fan-shelter clip and the
routing on the heat sink.
6. Install the drive cage .
7. Install the front bezel .
8. Install the cover .
9. Follow the procedures in After Working Inside Your Computer .
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