Owners Manual

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 single-rank memory modules, the available system memory is: 3/4
(ranks/channel) × 16 (memory modules) × 4 GB = 48 GB, and not 16 (memory modules) × 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.
Related concepts
System Setup on page 26
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.
Table 29. Memory configurations—single processor
System
Capacity (in
GB)
DIMM Size
(in GB)
Number of
DIMMs
DIMM Rank,
Organization, and
Frequency
DIMM Slot Population
8 8 1
1R, x8, 2400 MT/s A1
16 8 2
1R, x8, 2400 MT/s A1, A2
16 1
2R, x8, 2400 MT/s A1
32 8 4
1R, x8, 2400 MT/s A1, A2, A3, A4
16 2
2R, x8, 2400 MT/s A1, A2
32 1
2R, x4, 2400 MT/s A1
48 8 6
1R, x8, 2400 MT/s A1, A2, A3, A4, A5, A6
16 3
2R, x8, 2400 MT/s A1, A2, A3
64 8 8
1R, x8, 2400 MT/s A1, A2, A3, A4, A5, A6, A7, A8
16 4
2R, x8, 2400 MT/s A1, A2, A3, A4
32 2
2R, x4, 2400 MT/s A1, A2
96 16 6
2R, x8, 2400 MT/s A1, A2, A3, A4, A5, A6
32 3
2R, x4, 2400 MT/s A1, A2, A3
128 16 8
2R, x8, 2400 MT/s A1, A2, A3, A4, A5, A6, A7, A8
32 4
2R, x4, 2400 MT/s A1, A2, A3, A4
192 32 6
2R, x4, 2400 MT/s A1, A2, A3, A4, A5, A6
256 32 8
2R, x4, 2400 MT/s A1, A2, A3, A4, A5, A6, A7, A8
64 Installing and removing system components