System memory
The R740/R740xd supports DDR4 registered DIMMs (RDIMMs), load reduced DIMMs (LRDIMMs) and non-volatile dual in-line DIMM-Ns
(NVDIMM-Ns). System memory holds the instructions that are executed by the processor.
NOTE: MT/s indicates DIMM speed in MegaTransfers per second.
Memory bus operating frequency can be 2666 MT/s, 2400 MT/s, or 2133 MT/s depending on the following factors:
• DIMM type (RDIMM or LRDIMM)
• Number of DIMMs populated per channel
• System prole selected (for example, Performance Optimized, or Custom [can be run at high speed or lower])
• Maximum supported DIMM frequency of the processors
The R740/R740xd system contains 24 memory sockets split into two sets of 12 sockets, one set per processor. Each 12-socket set is
organized into six channels. In each channel, the release tabs of the rst socket are marked white, and the second socket black.
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