DIMM Population Rules

The population rules for adding DIMMs to the server are as follows:

• The server supports 64 GB quad-rank (QR) Load-Reduced DIMMs (LRDIMMs), 32-GB dual-rank (DR), and 16-GB DR Registered DIMMs (RDIMMs).

• Do not mix 64-GB LRDIMMs and 16-GB or 32-GB RDIMMs in the same server. If the server has 64-GB LRDIMMs installed, you cannot install 16 GB or 32 GB RDIMMs and vice versa.

• Do not mix different sizes or types of DDR4 DIMMs.

• Within a memory channel, DIMMs must be populated in the black sockets first, and then in the white sockets.

• If you are installing a mix of RDIMM sizes (for example, 16-GB and 32-GB), install the larger size RDIMMs first, then the smaller RDIMMs, until all of the RDIMMs are installed.

• The server will operate properly with a minimum of one DIMM installed per processor.

The following illustration shows the location of the memory buffers, the groups of DIMM slots, and the slots assigned to each channel.

Call Out	Description
1	DIMM Banks A, B, C
2	DIMM Banks D, E, F
3	Channel F, Slot 0, DIMM 0
4	Channel F, Slot 1, DIMM 1
5	Channel E, Slot 0, DIMM 2
6	Channel E, Slot 1, DIMM 3
7	Channel D, Slot 0, DIMM 4
8	Channel D, Slot 1, DIMM 5
9	Channel A, Slot 0, DIMM 6
10	Channel A, Slot 1, DIMM 7
11	Channel B, Slot 0, DIMM 8
12	Channel B, Slot 1, DIMM 9
13	Channel C, Slot 0, DIMM 10
14	Channel C, Slot 1, DIMM 11