Locate the two rubber mounts on the system fan assembly that attach to the chassis. Carefully remove these rubber mounts from the rear of the chassis by breaking them or cutting them with scissors.
Lift the system fan assembly out of the chassis.
When installing your new system fan assembly, use the new rubber mounts that come with the new fan.
Install the two short rubber mounts in the new system fan assembly as shown in the figure below.
Install the two long rubber mounts into the rear of the chassis. Push the mounts through the holes of the chassis. If necessary, pull the mounts through the holes from inside the chassis.
To install the new system fan assembly into the chassis, align the open holes in the system fan assembly with the long rubber mounts in the chassis. Pull the rubber mounts through the holes in the system fan assembly until the fan is in place.
Once the system fan assembly is secure, you should remove the extra rubber from the mounts.
Connect the system fan assembly cable to the fan connector on the system board.