SOYO SY-7VCA - Manual (Page 43)

Hardware Installation SY-7VCA
39
(2) Chassis Cooling Fan
Some chassis also feature a cooling fan. This Motherboard features a
CHAFAN connector to provide 12V power to the chassis fan. Connect the
cable from the chassis fan to the CHAFAN 3-pin connector. Install
according to the following pin assignment:
Note: CPUFAN must be installed for this Motherboard, CHAFAN is
optional.
Chassis Cooling Fan
SENSOR 12V GND
1 3 2