Fan Power Connector: Cpufan - MSI MICRO NLX BX4 User Manual

2.1-6 Fan Power Connector: CPUFAN

This connector support system cooling fan with +12V. It supports three pin
head connector. When connecting the wire to the connector, always take
note that the red wire is the positive and should be connected to the +12V,
the black wire is Ground and should be connected to GND. If your
mainboard had a System Hardware Monitor chipset on-board, you must use
a specially designed fan with speed sensor to take advantage of the CPU fan
control.
Note: For fans with speed sensor, every rotation of the fan will send out 2
pulses. System Hardware monitor will count and report the fan
rotation speed.
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