Dell 23.8" OptiPlex 7410 All-in-One Desktop Computer (Gray) - Manual (Page 73)

Installing the fan
Prerequisites
If you are replacing a component, remove the existing component before performing the installation process.
About this task
The following image(s) indicate the location of the fan and provides a visual representation of the installation procedure.
Steps
1. Place the fan on the display-assembly base.
2. Align the screw holes on the fan with the screw holes on the display-assembly base.
3. Replace the three screws (M3x5) that secure the fan to the display-assembly base.
4. Connect the fan cable (FAN CPU) to the system board.
5. Route the processor-power cable (ATX CPU) through the routing guide on the chassis.
6. Connect the processor-power cable (ATX CPU) to the system board.
Next steps
1. Install the system-board shield .
2. Install the back cover .
3. Install the stand .
4. Follow the procedure in After working inside your computer .
Removing and installing Customer Replaceable Units (CRUs) 73