Intel Core 2 Duo E7300 BX80570E7300 User Manual

Thermal and Mechanical Design Guidelines   

 65 

In the Intel 965 Express Family Chipset a new control algorithm for fan speed control 

is being introduced. It is composed of an Intel Management Engine (ME) in the 

Graphics Memory Controller Hub (GMCH) which executes the Intel Quiet System 

Technology (Intel QST) algorithm and the ICH8 containing the sensor bus and fan 

control circuits. 

The ME provides integrated fan speed control in lieu of the mechanisms available in a 

SIO or a stand-alone ASIC. The Intel QST is time based as compared to the linear or 

state control used by the current generation of FSC devices. 

A short discussion of Intel QST will follow along with thermal solution design 

recommendations. For a complete discussion of programming the Intel QST in the ME 

Consult the Intel

Manual.  

Note:  Fan speed control algorithms and Intel QST in particular rely on a thermal solution 

being compliant to the processor thermal profile. It is unlikely that any fan speed 
control algorithm can compensate for a non-compliant thermal solution. See Chapter 

6 for thermal solution requirements that should be met before evaluating 

or configuring a system with Intel QST. 

The objective of Intel QST is to minimize the system acoustics by more closely 

controlling the thermal sensors to the corresponding processor or chipset device 

T

CONTROL

 value. This is achieved by the use of a Proportional-Integral-Derivative (PID) 

control algorithm and a Fan Output Weighting Matrix. The PID algorithm takes into 

account the difference between the current temperature and the target (T

CONTROL

), the 

rate of change and direction of change to minimize the required fan speed change. 

The Fan Output Weighting Matrix uses the effects of each fan on a thermal sensor to 

minimize the required fan speed changes 

7-1 shows in a very simple manner how Intel QST works. See the Intel Quiet 

 QST) Configuration and Tuning Manual for a detail 

discussion of the inputs and response.