IBM Intel Xeon E5606 49Y3775 User Manual
Product codes
49Y3775
Intel
®
Xeon
®
Processor 5600 Series Datasheet Volume 1
133
Thermal Specifications
modulation is automatically engaged as part of the TCC activation when the
Frequency/VID targets are at their minimum settings. It may also be initiated by
software at a configurable duty cycle.
Frequency/VID targets are at their minimum settings. It may also be initiated by
software at a configurable duty cycle.
7.2.3
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 Adaptive Thermal Monitor feature. On-Demand
mode is intended as a means to reduce system level power consumption. Systems
must not rely on software usage of this mechanism to limit the processor temperature.
If bit 4 of the IA32_CLOCK_MODULATION MSR is set 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 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 Adaptive 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.
the processor to reduce its power consumption. This mechanism is referred to as “On-
Demand” mode and is distinct from the Adaptive Thermal Monitor feature. On-Demand
mode is intended as a means to reduce system level power consumption. Systems
must not rely on software usage of this mechanism to limit the processor temperature.
If bit 4 of the IA32_CLOCK_MODULATION MSR is set 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 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 Adaptive 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.
7.2.4
PROCHOT# Signal
An external signal, PROCHOT# (processor hot), is asserted when the processor core
temperature has reached its maximum operating temperature. If Adaptive Thermal
Monitor is enabled (note it 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#.
temperature has reached its maximum operating temperature. If Adaptive Thermal
Monitor is enabled (note it 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#.
The PROCHOT# signal is bi-directional in that it can either signal when the processor
(any core) has reached its maximum operating temperature or be driven from an
external source to activate the TCC. The ability to activate the TCC via PROCHOT# can
provide a means for thermal protection of system components.
(any core) has reached its maximum operating temperature or be driven from an
external source to activate the TCC. The ability to activate the TCC via PROCHOT# can
provide a means for thermal protection of system components.
As an output, PROCHOT# will go active when the processor temperature monitoring
sensor detects that one or more cores has reached its maximum safe operating
temperature. This indicates that the processor Thermal Control Circuit (TCC) has been
activated, if enabled. As an input, assertion of PROCHOT# by the system will activate
the TCC, if enabled, for all cores. TCC activation due to PROCHOT# assertion by the
system will result in the processor immediately transitioning to the minimum frequency
and corresponding voltage (using Freq/VID control). Clock modulation is not activated
in this case. The TCC will remain active until the system de-asserts PROCHOT#.
sensor detects that one or more cores has reached its maximum safe operating
temperature. This indicates that the processor Thermal Control Circuit (TCC) has been
activated, if enabled. As an input, assertion of PROCHOT# by the system will activate
the TCC, if enabled, for all cores. TCC activation due to PROCHOT# assertion by the
system will result in the processor immediately transitioning to the minimum frequency
and corresponding voltage (using Freq/VID control). Clock modulation is not activated
in this case. The TCC will remain active until the system de-asserts PROCHOT#.
PROCHOT# can allow voltage regulator (VR) thermal designs to target maximum
sustained current instead of maximum current. Systems should still provide proper
cooling for the VR, and rely on PROCHOT# only as a backup in case of system cooling
failure. The system thermal design should allow the power delivery circuitry to operate
within its temperature specification even while the processor is operating at its Thermal
Design Power.
sustained current instead of maximum current. Systems should still provide proper
cooling for the VR, and rely on PROCHOT# only as a backup in case of system cooling
failure. The system thermal design should allow the power delivery circuitry to operate
within its temperature specification even while the processor is operating at its Thermal
Design Power.