address is used on both channels such that an address error on any channel is detectable by bad
ECC. Lockstep Channel mode is the only RAS mode that supports x8 SDDC.
•Channel 3 is no function and can’t be populated in this mode.
•Follow the population rules described in independent mode.
•Lockstep mode needs the channel 1 & channel 2 with identical DIMM. DIMM slot populations within a
channel do not have to be identical but the same DIMM slot location across channel 1 and channel 2
must be the same. DIMM1A and DIMM2A should be the same type, size and manufacturer. DIMM1B
and DIMM2B memory should be the same type, size and manufacturer. DIMM1C and DIMM2C
memory should be the same type, size and manufacturer.
•Same rule is applied to the CPU2.
•3 DIMM per channel configuration is only available for single/dual rank RDIMM.
•Please refer to the User Guide for complete population for both single and dual processor
configurations.
.
Sparing mode:
•In this mode, if system detects degrading memory and system still not crash, the data in failed channel
will be copied to spare channel. Failed channel is then isolated and spare channel becomes active. But if
any uncorrectable error happens before the isolation, it will still cause the system stop normal operation.
•Channel 3 is the spare channel. Therefore, the effective size will be reduced by one-third.
•Follow the population rules described in independent mode.
•Sparing mode need all three channels with identical DIMMs. 1A, 2A and 3A should be the same type,
size and manufacturer. 1B, 2B and 3B memory should be the same type, size and manufacturer. 1C, 2C
and 3C memory should be the same type, size and manufacturer. Same rule is applied to CPU2.
•Memory sparing mode is only supported by Intel Xeon 5600 series processor. Intel Xeon 5500 series
processor does NOT support the memory sparing mode.
•3 DIMM per channel configuration is only available for single/dual rank RDIMM.
•Please refer to the User Guide for complete population for both single and dual processor
configurations.
Memory Identification
Generally, there are some memory information printed on the label of DIMM, but different vendor may have
different format. For example:
4GB 2Rx4 PC3-10600R xx xx xxx
1. Density
1GB, 2GB, 4GB, 8GB, 16GB
2. Rank
1R = Single Rank
2R = Dual Rank
4R = Quad Rank
Note: if any quad rank DIMM is used, maximum only 2 DIMM per channel can be supported
