Intel Xeon Phi Processor x200 Thermal/Mechanical Specification And Design Manual page 52

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in a system directly correlates to the processor's ability to meet thermal targets. For
this purpose, the parameter called T
that the long-term reliability of the processor is met while keeping the system-level
acoustic noise down.
When DTS values are less than T
value is a relative temperature to PROCHOT which is the maximum allowable
temperature before the thermal control circuit is activated. In this region, the DTS
value can be utilized to not only ensure specification compliance but also to optimize
FSC resulting in the lowest possible fan power and acoustics under any operating
condition. When DTS goes above T
temperature below T
The PECI temperature reading from the processor can be compared to this T
value. An FSC scheme can be implemented without compromising the long-term
reliability of the processor. The PECI command for DTS is GetTemp(). Through use of a
sign bit, the value returned from PECI is negative. The PECI command for T
RdPkgConfig(), Temperature Target Read, 15:8. The value returned from PECI, while
unsigned (positive), is negative by definition.
There are many different ways of implementing FSC; including methods based on
processor ambient temperature, processor DTS, or a combination of the two. If FSC is
based only on the processor ambient temperature, low acoustic targets can be
achieved under low ambient temperature conditions. However, the acoustics cannot be
optimized based on the behavior of the processor temperature. If FSC is based only on
the DTS, sustained temperatures above T
based both on the ambient and DTS, then ambient temperature can be used to scale
the fan RPM controlled by the DTS logic. This would result in an optimal acoustic
performance. Regardless of which scheme is employed, system designers must ensure
the T
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6.2.4.3 Tcontrol Relief
Intel may choose to provide T
to 0, as compared to the factory configured T
such plans at this time.
6.2.4.4 Thermal Excursion Power
Under fan failure or other anomalous thermal excursions, processor temperature
(either T
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360 hours per year without affecting long term reliability (life) of the processor. For
more typical thermal excursions, the thermal monitor is expected to control the
processor temperature by reducing the processor power level. These conditions should
not allow the processor to exceed the temperature at which the Thermal Control Circuit
(TCC) activation initially occurred.
Under more severe anomalous thermal excursions when the processor temperature
cannot be controlled at or below thermal profile by TCC activation, then data integrity is
not assured. At some higher thresholds, THERMTRIP_N will enable a shut down in an
attempt to prevent permanent damage to the processor.
Thermal test vehicles (TTVs) may be used to check anomalous thermal excursion
compliance. TTVs can be used to test and ensure the processor T
exceed T
fan failure.
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Intel Xeon Phi™ Processor x200 Product Family TMSDG
52
or to ensure compliance with the T
CONTROL
specification is met under all operational conditions.
CONTROL
or DTS) may exceed the thermal target for a duration totaling less than
at the anomalous power level for the condition of interest, such as
CASE_MAX
Thermal Specifications and Design Guidelines
is to be used in FSC designs to ensure
CONTROL,
the thermal target can be ignored. The DTS
CONTROL,
fan speed must increase to bring the sensor
CONTROL,
drive fans to maximum RPM. If FSC is
CONTROL
relief near product launch, T
values. However, there are no
CONTROL
profile.
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CONTROL
is
CONTROL
values closer
CONTROL
value does not
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Order Number: 334785-002