Intel Xeon Processor 2.80 GHz Thermal/Mechanical Design Guidelines

Thermal/Mechanical Reference Design
20 Dual-Core Intel
®
Xeon
®
Processor 2.80 GHz Thermal/Mechanical Design Guidelines
2.2.5 Altitude
The reference heatsink solutions will be evaluated at sea level (0 meters). The system designers
who need to account for altitude effects in the overall system thermal design must make sure that
either Thermal Profile A or B specification for the processor is met at the targeted altitude.
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 2.2.2, 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 2-6
depicts the relationship between T
CONTROL
and FSC methodology.
Table 2-2. Intel Reference Heatsink Performance Targets for the
Dual-Core Intel Xeon Processor 2.80 GHz
Thermal
Solution Type
Target Thermal
Profile
T
LA
Assumption
(°C)
TDP (W)
Thermal Performance Target, Ψca
(Mean + 3σ) (°C/W)
2U+ Form Factor Thermal Profile
A
40°C 135 0.234
1U Form Factor Thermal Profile
B
40°C 135 0.290