Owners Manual
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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 oer protection against a multi-bit uncorrectable error.
NOTE: Both Advanced ECC/Lockstep and Optimizer modes support Memory Sparing.
Sample memory configurations
The following tables list 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.
Table 4. Memory configurations—single processor
System Capacity
(in GB)
DIMM Size
(in GB)
Number of
DIMMs
DIMM Rank,
Organization, and
Frequency
DIMM Slot Population
64 16 4 2R, x8, 2400 MT/s,
2R, x8, 2133 MT/s,
2R, x8, 1866 MT/s
A1, A2, A3, A4
128 32 4 2R, x8, 2400 MT/s,
2R, x8, 2133 MT/s,
2R, x8, 1866 MT/s
A1, A2, A3, A4
128 16 8 2R, x8, 2400 MT/s,
2R, x8, 2133 MT/s,
2R, x8, 1866 MT/s
A1, A2, A3, A4, A5, A6, A7, A8
256 32 8 2R, x8, 2400 MT/s,
2R, x8, 2133 MT/s,
2R, x8, 1866 MT/s
A1, A2, A3, A4, A5, A6, A7, A8
Table 5. Memory configurations—two processors
System Capacity
(in GB)
DIMM Size
(in GB)
Number of
DIMMs
DIMM Rank,
Organization, and
Frequency
DIMM Slot Population
64 16 4 2R, x8, 2400 MT/s,
2R, x8, 2133 MT/s,
2R, x8, 1866 MT/s
A1, A2, B1, B2