Intel Quad-Core Xeon, Техническое описание

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Quad-Core Intel® Xeon® Processor 5300 Series Datasheet 101
Thermal Specifications
the same 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;
however, 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.
6.3.5 PROCHOT# Signal
An external signal, PROCHOT# (processor hot) is asserted when the processor die
temperature of any processor cores has reached its factory configured trip point. If
Thermal Monitor is enabled (note that 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 de-assertion of PROCHOT#. Refer to the Intel® 64 and IA-32 Architectures
Software Developer’s Manual and the Conroe and Woodcrest Processor Family BIOS
Writer’s Guide for specific register and programming details.
PROCHOT# is designed to assert at or a few degrees higher than maximum T
CASE
(as
specified by Thermal Profile A) 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
CASE
when dissipating TDP
power. There is no defined or fixed correlation between the PROCHOT# trip
temperature, or the case temperature. Thermal solutions must be designed to the
processor specifications and cannot be adjusted based on experimental measurements
of T
CASE
, or PROCHOT#.
6.3.6 FORCEPR# Signal
The FORCEPR# (force power reduction) input can be used by the platform to cause the
Quad-Core Intel® Xeon® Processor 5300 Series to activate the TCC. If the processor
supports Thermal Monitor 2 (TM2), and has Thermal Monitor 2 and Thermal Monitor
(TM) properly enabled, assertion of the FORCEPR# signal will immediately activate
Thermal Monitor 2. If the processor does not support Thermal Monitor 2, but has
Thermal Monitor properly enabled, FORCEPR# signal assertion will cause Thermal
Monitor to become active. Please refer to the Quad-Core Intel® Xeon® Processor 5300
Series NDA Specification Update to determine which processors support TM2 and
Conroe and Woodcrest Processor Family BIOS Writer’s Guide for details on enabling
these capabilities. Assertion of the FORCEPR# signal will activate TCC for all processor
cores. The TCC will remain active until the system deasserts FORCEPR#.
FORCEPR# is an asynchronous input, which can be employed to thermally protect other
system components. To use the voltage regulator (VR) as an example, TCC circuit
activation will reduce the current consumption of the processor and the corresponding
temperature of the VR.
It should be noted that assertion of FORCEPR# does not automatically assert
PROCHOT#. As mentioned previously, the PROCHOT# signal is asserted when a high
temperature situation is detected. A minimum pulse width of 500
µ
s is recommended
when FORCEPR# is asserted by the system. Sustained activation of the FORCEPR#
signal may cause noticeable platform performance degradation.
Refer to the appropriate platform design guidelines for details on implementing the
FORCEPR# signal feature.