MSI MS-6791 Manual page 21

Fan Power Connectors: CPUFAN1/CHSFAN1/NBFAN1/
PWRFAN1
The CPUFAN1 (processor fan), NBFAN1 (NorthBridge fan), PWRFAN1
(power fan) and CHSFAN1 (system fan) support system cooling fan with
+12V. It supports three-pin head connector. When connecting the wire to the
connectors, 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 the mainboard has 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.
SENSOR
+12V
GND
NBFAN1
MSI Reminds You...
Always consult the vendors for proper CPU cooling fan.
SENSOR
+12V
GND
CPUFAN1
Hardware Setup
SENSOR
+12V
GND
PWRFAN1
SENSOR
+12V
GND
CHSFAN1
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