Dell OptiPlex 3090 Ultra Service Manual page 120

Steps
1. Align the screws on the heat-sink with the screw holes on the system board.
2. In sequential order (as indicated on the heat sink), tighten the four captive screws that secure the heat sink to the system
board.
Next steps
1. Install the system board.
2. Install the solid-state drive
3. Install the memory module.
4. Install the WLAN card.
5. Install the system fan.
6. Install the cover.
7. Install the hard-drive assembly.
8. Install the device on Fixed stand/Pro 1 height-adjustable stand/Offset VESA mount/Pro 2 height-adjustable stand/Wall
mount.
9. Follow the procedure in
120 Removing and installing components
after working on your device.