Intel BX80635E52697V2 Manual Do Utilizador

Intel® Xeon® Processor E5-1600 v2/E5-2600 v2 Product Families

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Datasheet Volume One of Two

 

Demand mode, the duty cycle of the clock modulation is programmable via bits 3:0 of 

the same IA32_CLOCK_MODULATION MSR. In On-Demand mode, the duty cycle can 
be programmed from 6.25% on / 93.75% off to 93.75% on / 6.25% off in 6.25% 

increments. On-Demand mode may be used in conjunction with the Adaptive Thermal 

Monitor; however, if the system tries to enable On-Demand mode at the same time the 
TCC is engaged, the factory configured duty cycle of the TCC will override the duty 

cycle selected by the On-Demand mode.

An external signal, PROCHOT_N (processor hot), is asserted when the processor core 

temperature has reached its maximum operating temperature. If Adaptive Thermal 

Monitor is enabled (note it must be enabled for the processor to be operating within 
specification), the TCC will be active when PROCHOT_N is asserted. The processor can 

be configured to generate an interrupt upon the assertion or de-assertion of 

PROCHOT_N. Refer to the Intel® Xeon® Processor E5 v2 Product Family Processor 
Datasheet, Volume Two: Registers

 for specific register and programming details.

The PROCHOT_N signal is bi-directional in that it can either signal when the processor 

(any core) has reached its maximum operating temperature or be driven from an 
external source to activate the TCC. The ability to activate the TCC via PROCHOT_N can 

provide a means for thermal protection of system components. 

As an output, PROCHOT_N will go active when the processor temperature monitoring 
sensor detects that one or more cores has reached its maximum safe operating 

temperature. This indicates that the processor Thermal Control Circuit (TCC) has been 

activated, if enabled. As an input, assertion of PROCHOT_N by the system will activate 
the TCC, if enabled, for all cores. TCC activation due to PROCHOT_N assertion by the 

system will result in the processor immediately transitioning to the minimum frequency 

and corresponding voltage (using Freq/SVID control). Clock modulation is not activated 
in this case. The TCC will remain active until the system de-asserts PROCHOT_N.

PROCHOT_N can allow voltage regulator (VR) thermal designs to target maximum 

sustained current instead of maximum current. Systems should still provide proper 
cooling for the VR, and rely on PROCHOT_N as a backup in case of system cooling 

failure. The system thermal design should allow the power delivery circuitry to operate 

within its temperature specification even while the processor is operating at its Thermal 
Design Power. 

With a properly designed and characterized thermal solution, it is anticipated that 

PROCHOT_N will be asserted for very short periods of time when running the most 
power intensive applications. An under-designed thermal solution that is not able to 

prevent excessive assertion of PROCHOT_N in the anticipated ambient environment 

may cause a noticeable performance loss. Refer to the appropriate platform design 
guide and for details on implementing the bi-directional PROCHOT_N feature.

Regardless of whether Adaptive Thermal Monitor is enabled, in the event of a 

catastrophic cooling failure, the processor will automatically shut down when the silicon 
has reached an elevated temperature (refer to the THERMTRIP_N definition in 

). At this point, the THERMTRIP_N signal will go active 

and stay active. THERMTRIP_N activation is independent of processor activity and does 

not generate any Intel®

 

QuickPath Interconnect transactions. If THERMTRIP_N is