12VDC fan 80 x 80 x 15 mm, 3-pin (+12V, GND, tachometer), 34dB-A, 0.95m³/min

Attach one or more fans to the case to ensure good cooling of the computer. This is especially important in newer computers because of their high yields become very hot.
Has a built-in tachometer, which gives a signal to the motherboard. Rotational speed can be controlled by voltage, so the noise must be reduced noticeably.