General Memory Population Rules - Fujitsu PRIMERGY RX2540 M7 Upgrade And Maintenance Manual

10.2.2

General memory population rules

General memory population rules for 1DPC configuration
– All DIMMs must be DDR5 DIMMs modules.
– All DIMMs in a channel in across of a CPU socket must have the same
number of ranks (unless explicitly specified otherwise).
– All DDR5 DIMMs must be in the same speed per CPU socket.
– Mixing of x8 DIMMs and x4 DIMMS is not allowed in the same channel or
the same CPU socket.
– Mixing of non-3DS RDIMMs and 3DS RDIMMs is not allowed in platform.
– Mixing of 9x4 RDIMMs with other DIMMs is not allowed in platform.
– Mixing vendors in a system for RDIMMs and 3DS RDIMMs is allowed.
– DIMMs with different frequencies can be mixed in the system, but lowest
frequency determines the system memory speed.
– There should be at least one DDR5 DIMM per CPU socket.
– If only one DIMM is populated in a channel, then populate it in the slot
furthest away from CPU (i.e. the black slot).
Figure 196: Mixing of DIMM within an iMC - RDIMM
RX2540 M7 Upgrade and Maintenance Manual
Main memory
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