80546KF Datasheet, PDF (100/138 Pages) Intel Corporation – 64-bit Intel Xeon Processor MP with up to 8MB L3 Cache

Thermal Specifications
7.1.2 Thermal Metrology
The maximum and minimum case temperatures (T_CASE) specified in Table 7-1 are measured at the
geometric top center of the processor integrated heat spreader (IHS). Figure 7-2 illustrates the
location where T_CASE temperature measurements should be made. For detailed guidelines on
temperature measurement methodology, refer to the Processor Thermal/Mechanical Design
Guidelines.
Figure 7-2. Case Temperature (T_CASE) Measurement Location
Measure from edge of IHS
19.2 mm [0.756 in]
19.2 mm [0.756 in]
Measure T _CASE at this point
(geometric center of IHS)
53.34 mm FC-mPGA4 Package
Thermal grease should cover
entire area of IHS
7.2
7.2.1
Processor Thermal Features
Thermal Monitor
The Thermal Monitor feature helps control the processor temperature by activating the Thermal
Control Circuit (TCC) when the processor silicon reaches its maximum operating temperature. The
TCC reduces processor power consumption as needed by modulating (starting and stopping) the
internal processor core clocks. The Thermal Monitor (or Thermal Monitor 2) must be enabled for
the processor to be operating within specifications. The temperature at which Thermal Monitor
activates the thermal control circuit is not user configurable and is not software visible. Bus traffic
is snooped in the normal manner, and interrupt requests are latched (and serviced during the time
that the clocks are on) while the TCC is active.
When the Thermal Monitor is enabled and a high temperature situation exists (i.e. TCC is active),
the clocks will be modulated by alternately turning the clocks off and on at a duty cycle specific to
the processor (typically 30-50%). Clocks will not be off for more than 3 microseconds when the
TCC is active. Cycle times are processor speed dependent and will decrease as processor core
frequencies increase. A small amount of hysteresis has been included to prevent rapid active/
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64-bit Intel^® Xeon™ Processor MP with up to 8MB L3 Cache Datasheet