Lenovo ThinkSystem SR550 - Page 137

The following table shows the memory module population sequence for mirroring mode when one processor
(CPU1) is installed.
Table 16. Mirroring mode with one processor
Total
memory
modules
Processor 1 Total
memory
modules
6 5 4 3 2 1
2 3 2 2
3 3 2 1 3
4 5 4 3 2 4
6 6 5 4 3 2 1 6
The following table shows the memory module population sequence for mirroring mode when two
processors (CPU1 and CPU2) are installed.
Table 17. Mirroring mode with two processors
Total
memory
modules
Processor 2 Processor 2 Total
memo-
ry
mod-
ules
12 11 10 9 8 7 6 5 4 3 2 1
4 9 8 3 2 4
5 9 8 3 2 1 5
6 9 8 7 3 2 1 6
8 11 10 9 8 5 4 3 2 8
9 9 8 7 6 5 4 3 2 1 9
10 11 10 9 8 6 5 4 3 2 1 10
12 12 11 10 9 8 7 6 5 4 3 2 1 12
Rank sparing mode
In rank sparing mode, one rank of a memory module works as the spare rank for the other ranks on the same
channel. The spare rank is not available as system memory.
Notes:
• All memory modules to be installed must be the same type with the same capacity, frequency, voltage,
and number of ranks.
• Single-rank memory modules do not support rank sparing mode.
Table 18. Rank sparing mode with one processor
Total memory
modules
Processor 1
Total memory
modules
6 5 4 3 2 1
1 3 1
2 4 3 2
3 4 3 2 3
4 5 4 3 2 4
Chapter 3. Hardware replacement procedures 129