Intel X5550 AT80602000771AA Manuale Utente
Codici prodotto
AT80602000771AA
Thermal Specifications
104
Intel
®
Xeon
®
Processor 5500 Series Datasheet, Volume 1
6.2
Processor Thermal Features
6.2.1
Processor Temperature
A new feature in the Intel Xeon processor 5500 series is a software readable field in the
IA32_TEMPERATURE_TARGET register that contains the minimum temperature at
which the TCC will be activated and PROCHOT# will be asserted. The TCC activation
temperature is calibrated on a part-by-part basis and normal factory variation may
result in the actual TCC activation temperature being higher than the value listed in the
register. TCC activation temperatures may change based on processor stepping,
frequency or manufacturing efficiencies.
IA32_TEMPERATURE_TARGET register that contains the minimum temperature at
which the TCC will be activated and PROCHOT# will be asserted. The TCC activation
temperature is calibrated on a part-by-part basis and normal factory variation may
result in the actual TCC activation temperature being higher than the value listed in the
register. TCC activation temperatures may change based on processor stepping,
frequency or manufacturing efficiencies.
Note:
There is no specified correlation between DTS temperatures and processor case
temperatures; therefore it is not possible to use this feature to ensure the processor
case temperature meets the Thermal Profile specifications.
6.2.2
Adaptive Thermal Monitor
The Adaptive Thermal Monitor feature provides an enhanced method for controlling the
processor temperature when the processor silicon reaches its maximum operating
temperature. Adaptive Thermal Monitor uses Thermal Control Circuit (TCC) activation
to reduce processor power via a combination of methods. The first method
(Frequency/VID control) involves the processor adjusting its operating frequency (via
the core ratio multiplier) and input voltage (via the VID signals). This combination of
reduced frequency and VID results in a reduction to the processor power consumption.
The second method (clock modulation) reduces power consumption by modulating
(starting and stopping) the internal processor core clocks. The processor intelligently
selects the appropriate TCC method to use on a dynamic basis. BIOS is not required to
select a specific method (as with previous-generation processors supporting TM1 or
TM2).
The Adaptive Thermal Monitor feature must be enabled for the processor to be
operating within specifications. The temperature at which Adaptive Thermal
Monitor activates the Thermal Control Circuit is not user configurable and is not
software visible. Snooping and interrupt processing are performed in the normal
manner while the TCC is active.
With a properly designed and characterized thermal solution, it is anticipated that the
TCC would only be activated for very short periods of time when running the most
power intensive applications. The processor performance impact due to these brief
periods of TCC activation is expected to be so minor that it would be immeasurable. An
under-designed thermal solution that is not able to prevent excessive activation of the
TCC in the anticipated ambient environment may cause a noticeable performance loss,
and in some cases may result in a T
C
that exceeds the specified maximum temperature
which may affect the long-term reliability of the processor. In addition, a thermal
solution that is significantly under-designed may not be capable of cooling the
processor even when the TCC is active continuously. Refer to the appropriate
Thermal/Mechanical Design Guide for information on designing a compliant thermal
solution.
The duty cycle for the TCC, when activated by the Thermal Monitor, is factory
configured and cannot be modified. The Thermal Monitor does not require any
additional hardware, software drivers, or interrupt handling routines.
The following sections provide more details on the different TCC mechanisms used by
Intel Xeon processor 5500 series.