Intel Xeon 7130N LF80550KF0878M Data Sheet
Product codes
LF80550KF0878M
Thermal Specifications
Dual-Core Intel
®
Xeon
®
Processor 7000 Series Datasheet
71
operating temperature. Once the temperature has dropped below the maximum operating
temperature and the hysteresis timer has expired, the TCC goes inactive and clock modulation
ceases.
temperature and the hysteresis timer has expired, the TCC goes inactive and clock modulation
ceases.
With a thermal solution designed to meet the thermal profile, 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. 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 Dual-Core Intel
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. 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 Dual-Core Intel
®
Xeon
®
Processor 7000 Sequence Thermal/Mechanical
Design Guidelines for information on designing a 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.
cannot be modified. The Thermal Monitor does not require any additional hardware, software
drivers, or interrupt handling routines.
6.2.2
On-Demand Mode
The processor provides an auxiliary mechanism that allows system software to force the processor
to reduce its power consumption. This mechanism is referred to as “On-Demand” mode and is
distinct from the Thermal Monitor feature. On-Demand mode is intended as a means to reduce
system level power consumption. Systems utilizing the Dual-Core Intel Xeon processor 7000
series must not rely on software usage of this mechanism to limit the processor temperature.
to reduce its power consumption. This mechanism is referred to as “On-Demand” mode and is
distinct from the Thermal Monitor feature. On-Demand mode is intended as a means to reduce
system level power consumption. Systems utilizing the Dual-Core Intel Xeon processor 7000
series must not rely on software usage of this mechanism to limit the processor temperature.
If bit 4 of the IA32_CLOCK_MODULATION MSR is written to a ‘1’, the processor will
immediately reduce its power consumption via modulation (starting and stopping) of the internal
core clock, independent of the processor temperature. When using On-Demand mode, the duty
cycle of the clock modulation is programmable via bits 3:1 of the IA32_CLOCK_MODULATION
MSR. In On-Demand mode, the duty cycle can be programmed from 12.5% on/ 87.5% off to
87.5% on/12.5% off in 12.5% increments. On-Demand mode may be used in conjunction with the
Thermal Monitor. If the system tries to enable On-Demand mode at the same time the TCC is
engaged, the factory configured duty cycle of the TCC will override the duty cycle selected by the
On-Demand mode.
immediately reduce its power consumption via modulation (starting and stopping) of the internal
core clock, independent of the processor temperature. When using On-Demand mode, the duty
cycle of the clock modulation is programmable via bits 3:1 of the IA32_CLOCK_MODULATION
MSR. In On-Demand mode, the duty cycle can be programmed from 12.5% on/ 87.5% off to
87.5% on/12.5% off in 12.5% increments. On-Demand mode may be used in conjunction with the
Thermal Monitor. If the system tries to enable On-Demand mode at the same time the TCC is
engaged, the factory configured duty cycle of the TCC will override the duty cycle selected by the
On-Demand mode.
6.2.3
PROCHOT# Signal Pin
An external signal, PROCHOT# (processor hot), is asserted when the processor die temperature
has reached its factory configured trip point. If the Thermal Monitor is enabled (note that the
Thermal Monitor must be enabled for the processor to be operating within specification), the TCC
will be active when PROCHOT# is asserted. The processor can be configured to generate an
interrupt upon the assertion or deassertion of PROCHOT#. Refer to the IA-32 Intel
has reached its factory configured trip point. If the Thermal Monitor is enabled (note that the
Thermal Monitor must be enabled for the processor to be operating within specification), the TCC
will be active when PROCHOT# is asserted. The processor can be configured to generate an
interrupt upon the assertion or deassertion of PROCHOT#. Refer to the IA-32 Intel
®
Architecture
Software Developer’s Manual and the Prescott, Nocona and Potomac Processor BIOS Writer’s
Guide (BWG) for specific register and programming details.
Guide (BWG) for specific register and programming details.
PROCHOT# is designed to assert at or a few degrees higher than maximum T
CASE
(as specified by
the thermal profile) when dissipating TDP power, and cannot be interpreted as an indication of
processor case temperature. This temperature delta accounts for processor package, lifetime, and
manufacturing variations and attempts to ensure the Thermal Control Circuit is not activated below
maximum T
processor case temperature. This temperature delta accounts for processor package, lifetime, and
manufacturing variations and attempts to ensure the Thermal Control Circuit is not activated below
maximum T
CASE
when dissipating TDP power. There is no defined or fixed correlation between
the PROCHOT# trip temperature, the case temperature, or the thermal diode temperature. Thermal
solutions must be designed to the processor specifications and cannot be adjusted based on
experimental measurements of T
solutions must be designed to the processor specifications and cannot be adjusted based on
experimental measurements of T
CASE
, PROCHOT#, or Tdiode on random processor samples.