Depending on the server model, the server may come with a minimum of one 4 GB DIMM installed in slot 1. When you install additional DIMMs, install them in the order shown in the following table to optimize system performance.
In general, all four channels on the memory interface for each microprocessor can be populated in any order and have no matching requirements.
| Number of installed microprocessor | DIMM connector population sequence |
|---|---|
| One microprocessor installed | 1, 4, 9, 12, 2, 5, 8, 11, 3, 6, 7, 10 |
| Two microprocessors installed | 1, 13, 4, 16, 9, 21, 12, 24, 2, 14, 5, 17, 8, 20, 11, 23, 3, 15, 6, 18, 7, 19, 10, 22 |
For optimal performance:
Make sure all four memory channels of each microprocessor are populated. Each memory channels should be populated with the same type and amount of memory per channel. Each microprocessor socket should be populated with the same type and amount of memory per socket. 1DPC (one DIMM per channel) or 2DPC (two DIMM per channel) memory configuration are recommended. Unless there is a need for memory capacity over memory frequency, 3DPC (three DIMMs per channel) configuration is not recommended since 3DPC configuration forces the memory subsystem to run at a lower frequency (1600 MHz).
Refer to the Understanding and Optimizing Memory Performance for Intel Xeon Processor E5-2600 Series in IBM Flex System, System x, and BladeCenter Platforms white paper for the detail.