Intel CM8063501287403 User Manual

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

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Datasheet Volume One of Two

 

The normal operating state for the processor. The processor remains in the normal 

state when at least one of its cores is in the C0 or C1 state or when the platform has 

not granted permission to the processor to go into a low power state. Individual cores 
may be in lower power idle states while the package is in C0.

No additional power reduction actions are taken in the package C1 state. However, if 
the C1E substate is enabled, the processor automatically transitions to the lowest 

supported core clock frequency, followed by a reduction in voltage. Autonomous power 

reduction actions which are based on idle timers, can trigger depending on the activity 
in the system. 

The package enters the C1 low power state when:

• At least one core is in the C1 state.
• The other cores are in a C1 or lower power state. 

The package enters the C1E state when:

• All cores have directly requested C1E via MWAIT(C1) with a C1E sub-state hint.
• All cores are in a power state lower that C1/C1E but the package low power state is 

limited to C1/C1E via the PMG_CST_CONFIG_CONTROL MSR.

• All cores have requested C1 using HLT or MWAIT(C1) and C1E auto-promotion is 

enabled in POWER_CTL.

No notification to the system occurs upon entry to C1/C1E.

C2

C0

C1

C6

C3