Dell PowerEdge R900 - Manual (Page 94)

94 Installing System Components
Memory Mirroring Support
The system supports memory mirroring if 16 identical memory modules are
installed in the system. Mirroring must be enabled in the System Setup
program and can be used only if memory sparing is not enabled. In a mirrored
configuration, the total available system memory is one-half of the total
installed memory.
Table 3-1. Valid Memory Configurations
Branch 0 Branch 1
Number of
DIMMS Channel 0
(Riser A) Channel 1
(Riser B) Channel 2
(Riser C) Channel 3
(Riser D) Available Redundant
Memory Modes
1 DIMM A1 (riser only) (riser only) (riser only) None
4 DIMM A1 DIMM B1 DIMM C1 DIMM D1 None
8 DIMM A1
DIMM A2 DIMM B1
DIMM B2 DIMM C1
DIMM C2 DIMM D1
DIMM D2 None
12 DIMM A1
DIMM A2
DIMM A3 DIMM B1
DIMM B2
DIMM B3 DIMM C1
DIMM C2
DIMM C3 DIMM D1
DIMM D2
DIMM D3 None
16 DIMM A1
DIMM A2
DIMM A3
DIMM A4 DIMM B1
DIMM B2
DIMM B3
DIMM B4 DIMM C1
DIMM C2
DIMM C3
DIMM C4 DIMM D1
DIMM D2
DIMM D3
DIMM D4 Spare Mode / Mirror
Mode
20 DIMM A1
DIMM A2
DIMM A3
DIMM A4
DIMM A5 DIMM B1
DIMM B2
DIMM B3
DIMM B4
DIMM B5 DIMM C1
DIMM C2
DIMM C3
DIMM C4
DIMM C5 DIMM D1
DIMM D2
DIMM D3
DIMM D4
DIMM D5 Spare Mode / Mirror
Mode