Intel E5-2450 CM8062000862501 User Manual

Product codes
CM8062000862501
Page of 258
Intel® Xeon® Processor E5-1600/E5-2600/E5-4600 Product Families
95
Datasheet Volume One
Power Management
4.2.5.1
Package C0
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.
4.2.5.2
Package C1/C1E
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:
Table 4-9.
Coordination of Core Power States at the Package Level
Package C-State
Core 1
C0
C1
C3
C6
Core
 0 
C0
C0
C0
C0
C0
C1
C0
C1
1
Notes:
1. The package C-state will be C1E if all actives cores have resolved a core C1 state or higher. 
C3
C0
C3
C3
C6
C0
C3
C6
Figure 4-3. Package C-State Entry and Exit
C2
C0
C1
C6
C3