TYAN TOMCAT I7230B Manual page 59

3.3.4.2 Fan Control Selections
Auto Fan Control
This feature is used to set function of Auto Mode Fan Control.
Disabled / Enabled
J15/J14/J18/J13 Number of Pins Select
These features are used to select 3 or 4 pin fan connector. After the
setting, then you can use the function of "Auto Fan Control".
4 Pin / 3 Pin
59
http://www.tyan.com