Intel Xeon 7130N LF80550KF0878M Data Sheet

70

The maximum and minimum case temperatures (T

CASE

 are measured at the 

geometric top center of the processor IHS. 

 illustrates the location where T

CASE

 

temperature measurements should be made. For detailed guidelines on temperature measurement 
methodology, refer to the Dual-Core Intel

Design Guidelines.

The Thermal Monitor feature helps control the processor temperature by activating the 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 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/inactive transitions of the TCC when the processor temperature is near its maximum