Independent memory mode

Independent memory mode provides high performance memory capability. The memory channels can be populated with memory module in any order in independent mode. You can populate all eight channels on each processor in any order with no matching requirements. Individual channels can run at different memory module timings, but all channels must run at the same interface frequency.

Population rules

  1. Do not mix RDIMMs and 3DS RDIMMs.

  2. There should be at least one memory module per processor.

  3. There should be equal number of memory module for each memory type.

  4. Identical memory populations on all processors.

  5. x4 and x8 memory modules can be mixed in the same channel.

Memory module capacity guideline

In independent memory mode, the system can be installed with up to two types of memory capacity.

Attention:

Memory module numbers are divided into two groups, each should be populated with memory modules of the same capacity:

  • Group of memory module slot number 2, 4, 5, 7, 10, 12, 13, and 15.

  • Group of memory module slot number 1, 3, 6, 8, 9, 11, 14, and 16.

  • See Table 2 for more information.

With one processor and same capacity memory modules

The following table shows memory population sequence of independent mode for one processor and same capacity memory modules.

Table 1. Independent mode memory module population sequence for one processor with same capacity memory modules
Processor Processor 1
Memory module slot number 1 2 3 4 5 6 7 8
Total number of memory module 1   2            
2   2   4        
4*   2   4 5   7  
6 1 2   4 5   7 8
8*† 1 2 3 4 5 6 7 8
Note:

*Sub NUMA Clustering (SNC2) feature can only be enabled when DIMMs are populated in this specified sequence. The SNC2 feature can be enabled via UEFI.

DIMM configurations that support Software Guard Extensions (SGX), see Enable Software Guard Extensions (SGX) to enable this feature.

With one processor and different capacity memory modules

The following table shows memory population sequence of independent mode for one processor and different capacity memory modules.

Attention:

Memory module numbers are divided into two groups, each should be populated with memory modules of the same capacity:

  • Group of memory module slot number 2, 4, 5, 7, 10, 12, 13, and 15.

  • Group of memory module slot number 1, 3, 6, 8, 9, 11, 14, and 16.

  • See Table 2 for more information.
Table 2. Independent mode memory module population sequence for one processor with different capacity memory modules
Processor Processor 1
Memory module slot number 1 2 3 4 5 6 7 8
Total number of memory module 2   2 3        
4   2 3     6 7  

With two processor and same capacity memory modules

The following table shows memory population sequence of independent mode for two processors and same capacity memory modules.

Table 3. Independent mode memory module population sequence for two processors with same capacity memory modules
Processor Processor 1 Processor 2
Memory module slot number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Total number of memory module 2   2           15  
4   2   4       13   15  
8*   2   4 5   7   10   12 13   15  
12 1 2   4 5   7 8 9 10   12 13   15 16
16*† 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Note:

*Sub NUMA Clustering (SNC2) feature can only be enabled when DIMMs are populated in this specified sequence. The SNC2 feature can be enabled via UEFI.

DIMM configurations that support Software Guard Extensions (SGX), see Enable Software Guard Extensions (SGX) to enable this feature.

With two processor and different capacity memory modules

The following table shows memory population sequence of independent mode for two processors and different capacity memory modules.

Attention:

Memory module numbers are divided into two groups, each should be populated with memory modules of the same capacity:

  • Group of memory module slot number 2, 4, 5, 7, 10, 12, 13, and 15.

  • Group of memory module slot number 1, 3, 6, 8, 9, 11, 14, and 16.

  • See Table 2 for more information.
Table 4. Independent mode memory module population sequence for two processors with different capacity memory modules
Processor Processor 1 Processor 2
Memory module slot number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 c
Total number of memory module 4   2 3                   14 15  
8   2 3     6 7   10 11     14 15