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Independent mode installation order

In independent mode, memory channels can be populated with DIMMs in any order and you can populate all channels for each processor in any order with no matching requirements. Independent mode provides the highest level of memory performance, but lacks failover protection. The DIMM installation order for independent mode varies based on the number of processors and memory modules installed in the server.

Independent mode installation rules​

Follow the rules below when installing memory modules in independent mode:

  • All DDR5 memory modules must operate at the same speed in the same system.

  • Memory installation order must be identical between processors.

  • Memory modules from different vendors are supported.

  • In each memory channel, populate the slot farthest from the processor (slot 0) first.

  • All DIMMs must be all DDR5 RDIMMs.

  • x8 DIMMs and x4 DIMMs cannot be mixed in a system.

  • All memory modules to be installed must be of the same type.

  • All memory modules in a system must have the same number of ranks.

  • For the DIMM restrictions, see Supported DIMMs.

The following table shows the sequence of populating memory modules for independent mode when two processors (processor 1 and processor 2) are installed.

Table 1. Independent mode
Total DIMMsProcessor 1
161412107531
2 DIMMs7
8 DIMMs 14 107 3 
16 DIMMs161412107531
Total DIMMsProcessor 2
3230282623211917
2 DIMMs23
8 DIMMs 30 2623 19 
16 DIMMs3230282623211917

Supported DIMMs​

DIMM configurationSlot No.Supported DIMMs
2 DIMMs0

  • 16GB (1Rx8) / 32 GB (2Rx8) / 64 GB (2Rx4) RDIMMs

8 DIMMs0

  • 32GB (2Rx8) / 48 GB (2Rx8) RDIMMs,

  • 32GB (1Rx4)/64 GB (2Rx4) 10x4 RDIMMs

16 DIMMs0 or 1

  • 32GB (2Rx8) / 48GB (2Rx8) / 128 GB (2Rx4) RDIMMs

  • 32GB (1Rx4)/ 64 GB (2Rx4) / 94 GB (2Rx4) 10x4 RDIMMs

  • 32GB (2Rx8) MRDIMMs

  • 64GB (2Rx4) 10x4 MRDIMMs

  • 256 GB (4Rx4) 3DS RDIMMs