Dell PowerVault DR6000 - Manual (Page 37)

Memory Optimized (Independent Channel) Mode
This mode supports SDDC only for memory modules that use x4 device width and 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 4 GB dual-rank DIMMs, the
available system memory is: 3/4 (ranks/channel) × 16 (DIMMs) × 4 GB = 48 GB, and not 16 (DIMMs) × 4
GB = 64 GB.
NOTE: Memory sparing does not offer protection against a multi-bit uncorrectable error.
NOTE: Both Advanced ECC/Lockstep and Optimizer modes support Memory Sparing.
Memory Mirroring
Memory Mirroring offers the strongest DIMM reliability mode compared to all other modes, providing
improved uncorrectable multi-bit failure protection. In a mirrored configuration, the total available
system memory is one half of the total installed physical memory. Half of the installed memory is used to
mirror the active DIMMs. In the event of an uncorrectable error, the system will switch over to the
mirrored copy. This ensures SDDC and multi-bit protection.
Memory installation guidelines:
• Memory modules must be identical in size, speed, and technology.
• DIMMs installed in memory sockets with white release tabs must be identical and similar rule applies
for sockets with black and green release tabs. This ensures that identical DIMMs are installed in
matched pairs - for example, A1 with A2, A3 with A4, A5 with A6, and so on.
Memory Configuration
The following table shows the supported memory configuration for a two processor configuration that
follows the appropriate memory guidelines stated in this section.
NOTE: 2R in the following table indicates a single-rank DIMM.
Table 1. Memory Configuration
System
Capacity (in
GB)
DIMM Size (in
GB)
Number of
DIMMs
DIMM Rank,
Organization, and
Frequency
DIMM Slot Population
32 8 4 2R, x8, 1333 MT/s A1, A2, B1, B2
Removing Memory Modules
WARNING: The memory modules are hot to the touch for some time after the system has been
powered down. Allow time for the memory modules to cool before handling them. Handle the
memory modules by the card edges and avoid touching the components or metallic contacts on
the memory module.
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