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