The fan assembly is attached to the chassis by four rubber mounts. Carefully remove the four rubber mounts by breaking them or cutting them with scissors and then remove the fan assembly out of the chassis.
Install the new fan assembly by aligning the four rubber mounts of the fan assembly with the holes on the chassis and push the rubber mounts through the holes.
Pull on the tips of the rubber mounts until the fan assembly is in place.
Depending on which fan assembly you are replacing, reconnect the fan assembly cable to the adapter card fan assembly connector or the rear fan assembly connector on the system board. See "Locating parts on the system board".
If you are installing the hard disk drive fan assembly, reinstall the front bezel.