Independent memory mode with mixing ranks

Follow the memory module installation sequence in this section when installing memory modules with different ranks in independent memory mode.

Single-ranked RDIMMS can be mixed with dual-rank RDIMMs when there are 16 DIMMs populated for each processor (i.e., either 16 or 32 DIMMs in total).
If a memory channel has two DIMMs with different ranks, populate the DIMM with the higher number of rank in slot 0 (farthest from the processor) first.

With one processor

When installing DIMMs with different ranks with only one processor (Processor 1) installed, follow the sequence below and install higher rank DIMMs first; then, install the lower rank DIMMs into the remaining slots.

Table 1. Mixed-Rank DIMM slot installation sequence with one processor
Processor 1
Total DIMMs	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16
8 Dual-rank DIMMs	D²		D²		D²		D²			D²		D²		D²		D²
8 Single-rank DIMMs		S¹		S¹		S¹		S¹	S¹		S¹		S¹		S¹

Note

S: Single-rank RDIMM
D: Dual-rank RDIMM

With two processors

When installing DIMMs with different ranks with two processors installed, follow the sequence below and install higher rank DIMMs first; then, install the lower rank DIMMs into the remaining slots.

Table 2. Mixed-Rank DIMM slot installation sequence with two processors
Processor 1
Total DIMMs	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16
16 Dual-rank DIMMs	D²		D²		D²		D²			D²		D²		D²		D²
16 Single-rank DIMMs		S¹		S¹		S¹		S¹	S¹		S¹		S¹		S¹
Processor 2
Total DIMMs	32	31	30	29	28	27	26	25	24	23	22	21	20	19	18	17
16 Dual-rank DIMMs	D²		D²		D²		D²			D²		D²		D²		D²
16 Single-rank DIMMs		S¹		S¹		S¹		S¹	S¹		S¹		S¹		S¹

Note

S: Single-rank RDIMM
D: Dual-rank RDIMM

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Independent memory mode with mixing ranks

With one processor​

With two processors​

With one processor

With two processors