Lenovo Intel Xeon E5520 67Y0011 Manuale Utente

Thermal/Mechanical Design Guide

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compliance by ensuring that the processor Tcase value, as measured on the TTV, does 
not exceed Tcase_max_B at the anomalous power level for the environmental condition 
of interest. This anomalous power level is equal to 75% of the TDP limit.

Under fan failure or other anomalous thermal excursions, Tcase may exceed the 
thermal profile for a duration totaling less than 360 hours per year without affecting 
long term reliability (life) of the processor. For more typical thermal excursions, 
Thermal Monitor is expected to control the processor power level as long as conditions 
do not allow the Tcase to exceed the temperature at which Thermal Control Circuit 
(TCC) activation initially occurred. Under more severe anomalous thermal excursions 
when the processor temperature cannot be controlled at or below this Tcase level by 
TCC activation, then data integrity is not assured. At some higher threshold, 
THERMTRIP# will enable a shut down in an attempt to prevent permanent damage to 
the processor. Thermal Test Vehicle (TTV) may be used to check anomalous thermal 
excursion compliance by ensuring that the processor Tcase value, as measured on the 
TTV, does not exceed Tcase_max at the anomalous power level for the environmental 
condition of interest. This anomalous power level is equal to 75% of the TDP limit.

Intel does not test any third party software that reports absolute processor 
temperature. As such, Intel cannot recommend the use of software that claims this 
capability. Since there is part-to-part variation in the TCC (thermal control circuit) 
activation temperature, use of software that reports absolute temperature can be 
misleading.

See the Intel® Xeon® Processor 5500 Series Datasheet, Volume 1 for details 
regarding use of IA32_TEMPERATURE_TARGET register to determine the minimum 
absolute temperature at which the TCC will be activated and PROCHOT# will be 
asserted.