Memory Configuration guidelines for 13G PowerEdge servers - R430, T430 and R530

1. System Memory

Note: Unregistered Memory (UDIMM) is ONLY supported in following PowerEdge system models: T30, T130, R230, R330 and T330

The Dell PowerEdge R430, T430 and R530 supports DDR4 registered DIMMs (RDIMMs and LRDIMMs). More memory options are available than ever before with this range of servers — greater capacities, higher frequencies, and more flexibility. The R430, T430 and R530 supports up to 384GB of memory (12 DIMMs) and speeds up to 2400 MT/s, providing high performance in a variety of applications. High memory density means there is no compromise when it comes to virtualization.

NOTE: MT/s indicates DIMM speed in MegaTransfers per second.

Memory bus operating frequency can be 2400 MT/s, 2133 MT/s, 1866 MT/s, 1600 MT/s, or 1333 MT/s depending on the following factors:

•    System profile selected (for example, Performance Optimized, Custom, or Dense Configuration Optimized).

•    Maximum supported DIMM frequency of the processors.

The system contains 12 memory sockets split into four sets — two sets of four sockets and two sets of two sockets each. Each four-socket set is organized into two channels and each two–socket set is organized into one channel. In each channel of the four-socket set, the release levers of the first socket are marked white and the second socket black. In the two-socket set, each release lever is marked white.

NOTE: DIMMs in sockets A1 to A8 are assigned to processor 1 and DIMMs in sockets B1 to B4 are assigned to processor 2.

Figure 1: R430 Memory Sockets

Memory Channels are organized as follows:

The following table shows the memory populations and operating frequencies for the soppurted configurations.

2. General Memory Module Installation Guidelines

The system supports Flexible Memory Configuration, enabling the system to be configured and run in any valid chipset architectural configuration. The following are the recommended guidelines for installing memory modules:

•    x4 and x8 DRAM based DIMMs can be mixed. For more information, see Mode-specific guidelines.

•    Up to two dual- or single-rank RDIMMs can be populated per channel.

•    Populate DIMM sockets only if a processor is installed. For single-processor systems, sockets A1 to A8 are available. For dual-processor systems, sockets A1 to A8 and sockets B1 to B4 are available.

•    Populate all sockets with white release levers first, and then all the sockets with black release levers.

•    When mixing memory modules with different capacities, populate the sockets with memory modules with highest capacity first. For example, if you want to mix 4GB and 8GB DIMMs, populate 8GB DIMMs in the sockets with white release levers and 4GB DIMMs in the sockets with black release levers.

•    In a dual-processor configuration, the memory configuration for each processor should be identical through the first eight slots. For example, if you populate socket A1 for processor 1, then populate socket B1 for processor 2, and so on.

•    Memory modules of different capacities can be mixed provided other memory population rules are followed (for example, 4GB and 8GB memory modules can be mixed).

•    Mixing of more than two DIMM capacities in a system is not supported.

•    Populate two DIMMs per processor (one DIMM per channel) at a time to maximize performance.

3. Mode-Specific Guidelines

Four memory channels are allocated to each processor. The allowable configurations depend on the memory mode selected.

NOTE: You can mix x4 and x8 DRAM based DIMMs to support Reliability, Availability, and Serviceability (RAS) features. However, all guidelines for specific RAS features must be followed. x4 DRAM based DIMMs retain Single Device Data Correction (SDDC) in memory optimized (independent channel) mode. x8 DRAM based DIMMs require Advanced ECC mode to gain SDDC.

The following sections provide additional slot population guidelines for each mode:

Advanced ECC (Lockstep)

Advanced ECC mode extends SDDC from x4 DRAM based DIMMs to both x4 and x8 DRAMs. This protects against single DRAM chip failures during normal operation.

Memory installation guidelines:

•    Memory modules must be identical in size, speed, and technology.

•    DIMMs installed in memory sockets with white release levers must be identical and a similar rule applies for sockets with black release levers. This ensures that identical DIMMs are installed in matched pairs - for example, A1 with A2, A3 with A4, A5 with A6, and so on.

NOTE: Advanced ECC with Mirroring is not supported.

Memory Optimized (Independent Channel)

ModeThis mode supports SDDC only for memory modules that use x4 device width, and the mode does not impose any specific slot population requirements.

Memory Sparing

NOTE: To use memory sparing, this feature must be enabled in the System Setup.

In this mode, one rank per channel is reserved as a spare. If persistent, correctable errors are detected on a rank, the data from this rank is copied to the spare rank and the failed rank is disabled.

With memory sparing enabled, the system memory available to the operating system is reduced by one rank per channel. For example, in a dual-processor configuration with sixteen 4GB dual-rank DIMMs, the available system memory is: 3/4 (ranks/channel) × 16 (DIMMs) × 4GB = 48GB, and not 16 (DIMMs) x 4GB = 64GB.

NOTE: Memory sparing does not offer protection against a multi-bit uncorrectable error.

NOTE: Both Advanced ECC/Lockstep and Optimizer modes support Memory Sparing.

Sample Memory Configurations

The following tables show sample memory configurations for one and two processor configurations that follow the appropriate memory guidelines.

NOTE: 1R and 2R in the following tables indicate single- and dual-rank DIMMs respectively.

Supported Configurations

The PowerEdge R430, T430 and R530 will support Flexible Memory Configuration as long as it follows the chipset architectural rules. Dell Factory population will remain tightly controlled and follow the rules below:

•    If DIMMs of different speeds are mixed, all channels across all CPUs operate at the slowest DIMM’s common frequency.

•    Only one type of DIMM is allowed per system: RDIMM, or LRDIMMs. They cannot be mixed.

•    DIMM slot latches/ejection tabs are color coded per PowerEdge Behavioral Specification to aid identification of proper DIMM placement. First DIMM is white, second DIMM is black.

•    The DIMM sockets are placed 370 mils (10.02 mm) apart, center-to-center. This is done to maximize DIMM count, but may prevent >2 DRAM die stacking or multiple PCB (sandwiched) DIMMs.