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System memory
The system supports DDR4 registered DIMM (RDIMMs) slots, load reduced DIMM (LRDIMMs) slots and non-volatile dual in-line
DIMM-Ns (NVDIMM-Ns). System memory holds the instructions that are executed by the processor.
System memory population guidelines
NOTE: MT/s indicates DIMM speed in MegaTransfers per second.
Memory bus operating frequency can be 2666 MT/s, 2400 MT/s, 2133, or 1866 MT/s depending on the following factors:
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DIMM type (RDIMM or LRDIMM)
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Number of DIMM slots populated per channel
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System profile selected (for example, Performance Optimized, or Custom [can be run at any supported speed])
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Maximum supported DIMM frequency of the processors
The R840 contains 48 memory sockets split into four sets of 12 sockets, one set per processor.
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