AAEON EMB-B75A - Manual (Page 25)

2-17 Chapter 2: Motherboard information
CAUTION: Do not forget to connect the fan cables to the fan connectors.
Insufficient air flow inside the system may damage the motherboard
components. These are not jumpers! Do not place jumper caps on the fan
connectors!
NOTE: The CPU_FAN connector supports a CPU fan of maximum 2A (24 W)
fan power.
2. CPU and system fan connectors (4-pin CPU_FAN1, 4-pin SYS_FAN1)
Connect the fan cables to the fan connectors on the motherboard, ensuring
that the black wire of each cable matches the ground pin of the connector.
EMB-B75A Fan connectors
SYS_FAN
PWM
SENSE
VCC GND
CPU_FAN
PWM
SENSE
VCC GND