Asus H170-PRO Manual page 31

11. CPU and chassis fan connectors (4-pin CPU_FAN, 4-pin CHA_FAN 1/2)
black wire of each cable matches the ground pin of the connector
H170-PRO
H170-PRO Fan connectors
ASUS H170-PRO
A
A
CPU_FAN CHA_FAN1
B
C
C
CHA_FAN2
GND
CHA FAN PWR
CHA FAN IN
+5V
B
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