Guidelines
Thermal Mechanical Design
22 Dual-Core Intel
®
Xeon
®
Processor 7000 Sequence Thermal /Mechanical Guidelines
2.3 Characterizing Cooling Solution Performance
Requirements
2.3.1 Fan Speed Control
Fan speed control (FSC) techniques to reduce system level acoustic noise are a common practice in
server designs. The fan speed is one of the parameters that determine the amount of airflow
provided to the thermal solution. Additionally, airflow is proportional to a thermal solution’s
performance, which consequently determines the T
CASE
of the processor at a given power level.
Since the T
CASE
of a processor is an important parameter in the long-term reliability of a processor,
the FSC implemented in a system directly correlates to the processor’s ability to meet the Thermal
Profile and hence the long-term reliability requirements. For this purpose, the parameter called
T
CONTROL
as explained in Section 2.2.4, is to be used in FSC designs to ensure that the long-term
reliability of the processor is met while keeping the system level acoustic noise down. Figure 2-8
depicts the relationship between T
CONTROL
and FSC methodology.
T
LA
40 °C
Pressure Drop 0.15 Inches of
H
2
O
Altitude Sea-level Heatsink designed at 0 meters
Airflow 23 CFM Airflow through the heatsink fins
T
CASE_MAX
76 °C In case of conflict, Datasheet supersedes
TMDG.
T
CASE_MAX
@
Pcontrol_base
50 °C Pcontrol_base = 27 W
Table 2-3. Intel Reference Heatsink Performance Targets for the
Dual-Core Intel® Xeon® Processor 7000 Sequence (Sheet 2 of 2)
Parameter
Maximum Unit Notes
Figure 2-8. T
CONTROL
and Fan Speed Control
Pcontrol_base
TDP
T
CASE
MAX
T
CASE
@
Pcontrol_base
Power
Thermal Profile
T
CASE
@ T
CONTROL
Pcontrol
2
Fan speed control region
1
Pcontrol_base
TDP
T
CASE
MAX
T
CASE
@
Pcontrol_base
Power
Thermal Profile
T
CASE
@ T
CONTROL
Pcontrol
2
Fan speed control region
1
T
CASE
MAX
T
CASE
MAX@T
CONTROL
T
CASE
MAX@
Pcontrol_base
Pcontrol_base
TDP
T
CASE
MAX
T
CASE
@
Pcontrol_base
Power
Thermal Profile
T
CASE
@ T
CONTROL
Pcontrol
2
Fan speed control region
1
Pcontrol_base
TDP
T
CASE
MAX
T
CASE
@
Pcontrol_base
Power
Thermal Profile
T
CASE
@ T
CONTROL
Pcontrol
2
Fan speed control region
1
T
CASE
MAX
T
CASE
MAX@T
CONTROL
T
CASE
MAX@
Pcontrol_base