Intel 9150N NE80567KE025015 User Manual

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their cooling solution design. See Intel® Itanium® Processor 9300 Series Processor 
Thermal Mechanical Design Guide for additional guidance on implementing a compliant 
processor thermal solution.

THERMWARN is the temperature beyond which data integrity is not guaranteed and 
PROCHOT_N remains asserted.

The Intel Itanium processor 9300 series protects itself from catastrophic overheating 
by use of an internal thermal sensor. The sensor trip point is set well above the 
maximum operating temperature to ensure that there are no false trips. The Intel 
Itanium processor 9300 series will issue THERMTRIP_N and stop all execution when the 
junction temperature exceeds a safe operating level. At this point THERMTRIP_N is 
asserted. If THERMTRIP_N is asserted, processor voltages (VCCCORE, VCCUNCORE, 
AND VCCCACHE) must be removed within the timeframe defined in 

.

Data will be lost or corrupt, and transaction time outs will occur if the Intel Itanium 
processor 9300 series goes into thermal trip. The part that shuts down may still have 
pending snoops or memory reads that the other sockets in the partition may have 
requested.

Once THERMTRIP_N is asserted, the Intel Itanium processor 9300 series remains 
stopped until RESET_N is asserted. If the die temperature has dropped below the trip 
level, a RESET_N pulse can be used to reset the processor. If the temperature has not 
dropped below the trip level, the processor will continue to drive THERMTRIP_N and 
remain stopped. It is recommended to allow the processor case temperature to drop 
below the specified design target before issuing a reset to the processor. Please see 

 for details on the case temperature.

In a partitioned system, sockets in the same partition are in the same coherency 

domain, so they cannot continue to operate if even one of the processors asserts 

THERMTRIP_N and shuts down. Moreover, a cold reset is required to get the part back 

up after a THERMTRIP event. Because cold reset will reset all the sockets in the 

partition, the other sockets cannot continue running without a reset event. 

The temperature at PROCHOT represents the maximum normal operating temperature 
of the processor. PROCHOT_N is asserted when the processor temperature is greater 
than or equal to T

PROCHOT.

PROCHOT_N is a signal from the processor to the platform indicating that the processor 
has detected an over-temperature condition and it is taking corrective measures. This 
pin is not asserted when FORCEPR_N or VR_THERMALERT_N is asserted unless the 
thermal system has detected a PROCHOT condition independent of those input signals. 
The condition may occur due to any of the following conditions:

• The thermal environment is outside of the limits defined for full performance 

operation.

• The processor power consumption is unbalanced due to very high activity factors in 

some cores coupled with very low activity factors in others.