Intel Core 2 Extreme QX6850 BX80569QX6850 Manuel D’Utilisation

120

the motherboard that sends out a PWM control signal to the 4

th

 pin of the connector 

labeled as CONTROL. The fan speed is based on a combination of actual processor 

temperature and thermistor temperature. 

If the 4-wire PWM controlled fan in the TMA solution is connected to a 3-pin baseboard 

processor fan header it will default back to a thermistor controlled mode, allowing 

compatibility with existing 3-pin baseboard designs. Under thermistor controlled mode, 

the fan RPM is automatically varied based on the T

inlet

 temperature measured by a 

thermistor located at the fan inlet.

For more details on specific motherboard requirements for 4-wire based fan speed 

control, refer to the appropriate Thermal and Mechanical Design Guidelines (see