Intel Core 2 Duo E7300 BX80570E7300 User Manual
Product codes
BX80570E7300
Intel® Quiet System Technology (Intel® QST)
70
Thermal and Mechanical Design Guidelines
7.3
Intel
®
QST Configuration & Tuning
Initial configuration of the Intel QST is the responsibility of the board manufacturer.
The SPI flash should be programmed with the hardware configuration of the
motherboard and initial settings for fan control, fan monitoring, voltage and thermal
monitoring. This initial data is generated using the Intel provided Configuration Tool.
At the system integrator the Configuration Tool can be used again but this time to
tune the Intel QST subsystem to reflect the shipping system configuration. In the
tuning process the Intel QST can be modified to have the proper relationships between
the installed fans and sensors in the shipping system. A Weighting Matrix Utility and
Intel QST Log program are planned to assist in optimizing the fan management and
achieve acoustic goal.
See your Intel field sales representative for availability of these tools.
7.4
Fan Hub Thermistor and Intel
®
QST
There is no closed loop control between Intel QST and the thermistor, but they can
work in tandem to provide the maximum fan speed reduction. The BTX reference
design includes a thermistor on the fan hub. This Variable Speed Fan curve will
determine the maximum fan speed as a function of the inlet ambient temperature and
by design provides a
CA
sufficient to meet the thermal profile of the processor. Intel
QST, by measuring the processor Digital thermal sensor will command the fan to
reduce speed below the VSF curve in response to processor workload. Conversely if
the processor workload increases the FSC will command the fan using the PWM duty
cycle to accelerate the fan up to the limit imposed by the VSF curve. Care needs to be
taken in BTX designs to ensure the fan speed at the minimum operating speed
provides sufficient air flow to support the other system components.
Figure
7-5. Digital Thermal Sensor and Thermistor
Fan S
p
e
e
d
(R
PM
)
Inlet Temperature (°C)
Full
Speed
30
38
Min.
Operating
Variable Speed Fan (VSF) Curve
Fan Speed
Operating Range
with FSC
Operating Range
with FSC
34
Min %
Fa
n
S
peed
(%
P
W
M Du
ty
Cy
cle
)
100 %
Fan S
p
e
e
d
(R
PM
)
Inlet Temperature (°C)
Full
Speed
30
38
Min.
Operating
Variable Speed Fan (VSF) Curve
Fan Speed
Operating Range
with FSC
Operating Range
with FSC
34
Min %
Fa
n
S
peed
(%
P
W
M Du
ty
Cy
cle
)
100 %