Intel QX9770 - Core 2 Extreme Quad-Core Processor User Manual

Intel® Quiet System Technology (Intel® QST)
Thermal and Mechanical Design Guidelines 59
Figure 22. PID Controller Fundamentals
Proportional
Error
Derivative (Slope)
Integral (time averaged)
Proportional
Error
Derivative (Slope)
Integral (time averaged)
Proportional
Error
Derivative (Slope)
Integral (time averaged)
Proportional
Error
Derivative (Slope)
Integral (time averaged)
RPM Temperature
Time
+ dPWM
+ dPWM
+ dPWM
+ dPWM
+ dPWM
+ dPWM
-
-
dPWM
dPWM
-
-
dPWM
dPWM
-
-
dPWM
dPWM
Actual
Temperature
Actual
Temperature
Fan
Speed
Fan
Speed
Limit
Temperature
Limit
Temperature
For a PID algorithm to work limit temperatures are assigned for each temperature
sensor. For Intel QST the T
CONTROL
for the processor and chipset are to be used as the
limit temperature. The ME will measure the error, slope and rate of change using the
equations below:
•
Proportional Error (P) = T
LIMIT
– T
ACTUAL
• Integral (I) = Time averaged error
• Derivative (D) = ΔTemp / ΔTime
Three gain values are used to control response of algorithm.
• Kp = proportional gain
• Ki = Integral gain
•
Kd = derivative gain
The Intel
®
Quiet System Technology (Intel
®
QST) Configuration and Tuning Manual
provides initial values for the each of the gain constants. In addition it provides a
methodology to tune these gain values based on system response.
Finally the fan speed change will be calculated using the following formula:
ΔPWM = -P*(Kp) – I*(Ki) + D*(Kd)

Intel QX9770 - Core 2 Extreme Quad-Core Processor Specifications

General

Processor Number	QX9770
Number of Cores	4
Thread Count	4
Clock Speed	3.2 GHz
L2 Cache	12 MB
Bus Speed	1600 MHz
Thermal Design Power (TDP)	136 W
Socket	LGA 775
Manufacturing Process	45 nm
Max Operating Temperature	64.5°C
Virtualization Technology	Yes
64-bit Support	Yes
Instruction Set	SSE4.1
Memory Channels	2
Memory Types	DDR3