Asus AW171 - Manual (Page 35)

ASUS SK8N motherboard user guide 2-9
2.4.4 Connecting the CPU fan cable
When the fan, heatsink, and the retention mechanism are in place,
connect the CPU fan cable to the connector on the motherboard labeled
CPU_FAN1.
4. Push down the retention bracket lock on the retention mechanism to
secure the heatsink and fan to the module base.
Don’t forget to connect the CPU fan connector! Hardware monitoring
errors may occur if you fail to plug this connector.
CPU Fan Connector
(CPU_FAN1)