Intel E5-1600, E5-4600 States, Socket ID Strapping, Power Impact of Peci Commands vs. C-states

The client address may not be changed after PWRGOOD assertion, until the next power cycle on the processor. Removal of a processor from its socket or tri-stating a processor will have no impact to the remaining non-tri-stated PECI client addresses. Since each socket in the system should have a unique PECI address, the SOCKET_ID strapping is required to be unique for each socket.

Table 2-17. SOCKET ID Strapping

SOCKET_ID[1] Strap	SOCKET_ID[0] Strap	PECI Client Address
Ground	Ground	0x30
Ground	VTT	0x31
VTT	Ground	0x32
VTT	VTT	0x33

2.5.3.4C-states

The processor PECI client may be fully functional in most core and package C-states.

•The Ping(), GetDIB(), GetTemp(), RdPkgConfig() and WrPkgConfig() commands have no measurable impact on CPU power in any of the core or package C-states.

•The RdIAMSR() command will complete normally unless the targeted core is in a C- state that is C3 or deeper. The PECI client will respond with a completion code of 0x82 (see Table 2-22for definition) for RdIAMSR() accesses in core C-states that are C3 or deeper.

•The RdPCIConfigLocal(), WrPCIConfigLocal(), and RdPCIConfig() commands will not impact the core C-states but may have a measurable impact on the package C- state. The PECI client will successfully return data without impacting package C- state if the resources needed to service the command are not in a low power state.

—If the resources required to service the command are in a low power state, the PECI client will respond with a completion code of 0x82 (see Table 2-22for definition). If this is the case, setting the “Wake on PECI” mode bit as described in Section 2.5.2.6 can cause a package ‘pop-up’ to the C2 state and enable successful completion of the command. The exact power impact of a pop-up to C2 will vary by product SKU, the C-state from which the pop-up is initiated and the negotiated PECI bit rate.

Table 2-18. Power Impact of PECI Commands vs. C-states

Command	Power Impact
Ping()	Not measurable
GetDIB()	Not measurable
GetTemp()	Not measurable
RdPkgConfig()	Not measurable
WrPkgConfig()	Not measurable
RdIAMSR()	Not measurable. PECI client will not return valid data in core C-state that is C3 or deeper
RdPCIConfigLocal()	May require package ‘pop-up’ to C2 state
WrPCIConfigLocal()	May require package ‘pop-up’ to C2 state
RdPCIConfig()	May require package ‘pop-up’ to C2 state

Intel® Xeon® Processor E5-1600/E5-2600/E5-4600 Product Families	71
Datasheet Volume One