Memory module installation guidelines

The following notes describe the types of DIMMs that the compute node supports and other information that you must consider when you install DIMMs. This section applies to both RDIMMs and 3DS RDIMMs.

General memory module installation guidelines

The DIMM (memory) population sequences in this section show all of the memory population combinations that are supported by your compute node. Each processor in your compute node has four memory controllers, each memory controller has two memory channels, and each memory channel has one DIMM slot. To populate balanced memory configurations for the best memory performance, observe the following guidelines:

  • The operating speed of the compute node is determined by the operating mode, memory speed, memory ranks, memory population and processor.
  • The compute node only supports industry-standard double-data-rate 4 (DDR4), dynamic random-access memory (DRAM) registered dual in-line memory modules (RDIMMs) with error-correcting code (ECC). Confirm that the compute node supports the DIMM that you are installing (see Lenovo ServerProven website).
  • Do not mix RDIMMs and 3DS RDIMMs in the same compute node.
  • Install an equal number of DIMMs for each DIMM type.
  • You can use compatible DIMMs from various manufacturers in the same pair.
  • Install higher capacity (ranked) DIMMs first, following the specified population sequence.
  • When you install or remove DIMMs, the compute node configuration information changes. When you restart the compute node, the system displays a message that indicates that the memory configuration has changed. You can use the Setup utility to view the node configuration information, see System configuration for more information.
For more detailed installation guidelines and DIMM population sequences in the independent and memory mirroring mode, refer to