Nvm/Lrdimm - Fujitsu PRIMERGY TX2550 M5 Upgrade And Maintenance Manual

Main memory
– Not all possible configurations will be offered.
10.2.3.2

NVM/LRDIMM

NVM/LRDIMM is a new non-volatile DIMM memory that has read performance
characteristics close to DRAM, lower write performance, and larger memory
capacity. NVM/LRDIMM is populated in a DDR4 288 pin DIMM connector in a
DDR4 channel and utilizes the DDR-T protocol.
Supports the following operation modes:
– Memory mode (2LM)
– App Direct mode (1LM)
– Mixed mode (2LM), mixture of Memory and App Direct mode
Memory mode (2LM)
– In Memory mode NVM/LRDIMM are configured as volatile memory.
– In this mode DDR4 DIMMs act as "write back" cache to the NVM/LRDIMM
on the DIMM channel within the same memory controller only.
– Recommended DDR4 DRAM to NVM/LRDIMM capacity ratio is 1:8.
– Min 1 DDR4 DIMM + 1 NVM/LRDIMM per IMC.
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