3.1.3.3DIMM Population Rules and Supported DIMM Configurations

Notes:

Single channel mode is only tested and supported with a 512MB x8 FBDIMM installed in DIMM Slot A1.

The supported memory configurations must meet population rules defined above.

For best performance, the number of DIMMs installed should be balanced across both memory branches. For example: a four-DIMM configuration will perform better than a two-DIMM configuration and should be installed in DIMM slots A1, B1, C1, and D1. An eight-DIMM configuration will perform better then a six-DIMM configuration.

Although mixed DIMM capacities between channels are supported, Intel does not validate DIMMs in mixed DIMM configurations.

3.1.3.3.1Minimum Non-Mirrored Mode Configuration

The server board is capable of supporting a minimum of one DIMM installed. However, for system performance reasons, Intel’s recommendation is that at least two DIMMs be installed.

The following diagram shows the recommended minimum DIMM memory configuration. Populated DIMM slots are shown in gray.

Note: The server board supports single DIMM mode operation. Intel will only validate and support this configuration with a single 512 MB x8 FBDIMM installed in DIMM socket A1.

3.1.3.4Non-mirrored Mode Memory Upgrades

The minimum memory upgrade increment is two DIMMs per branch. The DIMMs must cover the same slot position on both channels. DIMMs pairs must be identical with respect to size, speed, and organization. DIMMs that cover adjacent slot positions do not need to be identical.

When adding two DIMMs to the configuration shown in Figure 13 (above), the DIMMs should be populated in DIMM sockets C1 and D1 as shown in the following figure. Populated DIMM sockets are shown in gray.

Branch 1

TP02301

Figure 14. Recommended Four DIMM Configuration

Functionally, DIMM sockets A2 and B2 could also have been populated instead of DIMM sockets C1 and D1. However, your system will not achieve equivalent performance. Figure 13 on the previous page, shows the supported DIMM configuration that is recommended because it allows both branches to operate independently and simultaneously. FBD bandwidth is doubled when both branches operate in parallel.

3.1.3.4.1Mirrored Mode Memory Configuration

When operating in mirrored mode, both branches operate in lock step. In mirrored mode, branch 1 contains a replicate copy of the data in branch 0. The minimum DIMM configuration to support memory mirroring is four DIMMs, populated as shown in Figure 14, above. All four DIMMs must be identical with respect to size, speed, and organization.

To upgrade a four-DIMM mirrored memory configuration, four additional DIMMs must be added to the system. All four DIMMs in the second set must be identical to the first with the exception of speed. The MCH will adjust to the lowest speed DIMM.