Dell OptiPlex 3080 Tower Service Manual page 64

Steps
1. To remove the dummy metal bracket, insert a flathead screwdriver in the hole of the bracket, push the bracket to release
the bracket, and then lift the bracket out from the system.
2. Insert the optional I/O module (Type-C/HDMI/VGA/DP/Serial) into its slot from the inside of your computer.
3. Connect the I/O cable to the connector on the system board .
4. Replace the two (M3X3) screws to secure the optional I/O module to the system.
Next steps
1. Install the fan duct.
2. Install the front bezel.
3. Install the side cover.
4. Follow the procedure in
64 Disassembly and reassembly
after working inside your computer.