Tcontrol And Fan Speed Control - Intel 5100 Series Instruction Manual

Figure 2-12. T
CONTROL
Fan Speed Control Region Fan Speed Control Region
Once the T
reading from the processor can be compared to this T
control scheme can be implemented as described in
the long-term reliability of the processor.
Table 2-7. Fan Speed Control, T
Condition
DTS≤ T
CONTROL
DTS>T
CONTROL
There are many different ways of implementing fan speed control, including FSC based
on processor ambient temperature, FSC based on processor Digital Thermal Sensor
(DTS) temperature or a combination of the two. If FSC is based only on the processor
ambient temperature, low acoustic targets can be achieved under low ambient
temperature conditions. However, the acoustics cannot be optimized based on the
behavior of the processor temperature. If FSC is based only on the Digital Thermal
Sensor, sustained temperatures above T
based both on ambient and Digital Thermal Sensor, ambient temperature can be used
to scale the fan RPM controlled by the Digital Thermal Sensor. This would result in an
optimal acoustic performance. Regardless of which scheme is employed, system
designers must ensure that the Thermal Profile specification is met when the processor
Digital Thermal Sensor temperature exceeds the T
30
and Fan Speed Control
T T MAX MAX
CASE CASE
T T @DTS= @DTS=
CASE CASE
T T
CONTROL CONTROL
T T MAX@ MAX@
CASE CASE
P P
_PROFILE_MIN _PROFILE_MIN
P P
_PROFILE_MIN _PROFILE_MIN
value is determined as explained earlier, the DTS temperature
CONTROL
CONTROL
FSC can adjust fan speed to maintain DTS = T
FSC should adjust fan speed to keep T
specification (increased acoustic region).
Dual-Core Intel® Xeon® Processor 5100 Series Thermal/Mechanical Design Guide
Thermal/Mechanical Reference Design
② ②
① ①
Power Power
CONTROL
Table 2-7
and DTS Relationship
FSC Scheme
CASE
drives fans to maximum RPM. If FSC is
CONTROL
CONTOL
Thermal Profile Thermal Profile
TDP TDP
value. A fan speed
without compromising
(low acoustic region).
CONTROL
at or below the Thermal Profile
value for a given processor.