Intel BX80605X3440 - Quad Core Xeon X3440, Reference

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Document Number: 424077 Revision: 2.0Thermal/Mechanical Specifications and Design Guidelines 37
Thermal Specifications
6
Thermal Specifications
The processor requires a thermal solution to maintain temperatures within its operating
limits. Any attempt to operate the processor outside these operating limits may result
in permanent damage to the processor and potentially other components within the
system. Maintaining the proper thermal environment is key to reliable, long-term
system operation.
A complete solution includes both component and system level thermal management
features. Component level thermal solutions can include active or passive heatsinks
attached to the processor integrated heat spreader (IHS).
This chapter provides data necessary for developing a complete thermal solution. For
more information on 1U collaboration thermal solution design, refer to
Chapter 8 .
6.1 Thermal Specifications
To allow the optimal operation and long-term reliability of Intel processor-based
systems, the processor must remain within the minimum and maximum case
temperature (T
CASE
) specifications as defined by the applicable thermal profile.
Thermal solutions not designed to provide this level of thermal capability may affect the
long-term reliability of the processor and system. For more details on thermal solution
design, refer to the
Chapter 8 .
The processors implement a methodology for managing processor temperatures which
is intended to support acoustic noise reduction through fan speed control and to assure
processor reliability. Selection of the appropriate fan speed is based on the relative
temperature data reported by the processor’s Digital Temperature Sensor (DTS). The
DTS can be read using the Platform Environment Control Interface (PECI) as described
in
Section 6.3 . Alternatively, when PECI is monitored by the PCH, the processor
temperature can be read from the PCH using the SMBus protocol defined in Embedded
Controller Support Provided by Platform Controller Hub (PCH)
. The temperature
reported over PECI is always a negative value and represents a delta below the onset of
thermal control circuit (TCC) activation, as indicated by PROCHOT# (see
Section 6.2 ,
Processor Thermal Features). Systems that implement fan speed control must be
designed to use this data. Systems that do not alter the fan speed only need to ensure
the case temperature meets the thermal profile specifications.
A single integer change in the PECI value corresponds to approximately 1 °C change in
processor temperature. Although each processors DTS is factory calibrated, the
accuracy of the DTS will vary from part to part and may also vary slightly with
temperature and voltage. In general, each integer change in PECI should equal a
temperature change between 0.9 °C and 1.1 °C.
Analysis indicates that real applications are unlikely to cause the processor to consume
maximum power dissipation for sustained time periods. Intel recommends that
complete thermal solution designs target the Thermal Design Power (TDP), instead of
the maximum processor power consumption. The Adaptive Thermal Monitor feature is
intended to help protect the processor in the event that an application exceeds the TDP
recommendation for a sustained time period. For more details on this feature, refer to