The system cooling fan is a Noctua NF-P12 120mm pulse-width modulation fan. This fan is no longer available to purchase, but the replacement Noctua NF-P12 Redux-1300 PWM 120mm Fan should be a drop-in replacement.

To remove the fan, first remove the long top screw in the LED / Button combo board. This screw holds the fan in place.

Once you've removed the retaining screw, the fan and shroud assembly will slide backwards and out of the mounting slots.

To remove the shroud from the fan, gently release the longer two clips from the right-hand side of the shroud.