System Memory - Dell EMC PowerEdge R640 Installation And Service Manual

Figure 31. Installing the cooling fan
Next steps
Install the air shroud.

System memory

The system 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 2667 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 profile selected (for example, Performance Optimized, or Custom [can be run at high speed or lower])
• Maximum supported DIMM frequency of the processors
Your 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 first socket are marked white, and the second socket black.
Dell EMC PowerEdge R640 Installation and Service Manual
Installing and removing system components
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