Memory mirrored channel mode replicates and stores data
on two pairs of DIMMs within two channels simultaneously.
In memory mirrored channel mode, the memory contents are mirrored
between Channel 0 and Channel 1 and also between Channel 2 and Channel
3. As a result of the mirroring, the total physical memory available
to the system is half of what is populated. Mirrored channel mode
requires that Channel 0 and Channel 1, and Channel 2 and Channel 3
must be populated identically with regards to size and organization.
DIMM slot populations within a channel do not have to be identical
but the same DIMM slot location across Channel 0 and Channel 1 and
across Channel 2 and Channel 3 must be populated the same.
If a failure occurs, the memory controller switches from the primary
pair of memory DIMMs to the backup pair of DIMMs. To enable memory
mirrored channel through the Setup utility, select . For more information, see
Using the Setup utility. When you use
the memory mirrored channel feature, consider the following information:
- When you use memory mirrored channel, you must install a pair
of DIMMs at a time. The two DIMMs in each pair must be identical in
size, type, and rank (single, dual, or quad), and organization, but
not in speed. The channels run at the speed of the slowest DIMM in
any of the channels.
- The maximum available memory is reduced to half of the installed
memory when memory mirrored channel is enabled. For example, if you
install 8 GB of memory using RDIMMs, only 4 GB of addressable memory
is available when you use memory mirrored channel.
The following table shows the installation sequence for memory
mirrored channel mode:
Table 1. Memory mirrored channel mode DIMM population sequence.
Two column table documenting the number
of installed microprocessor and DIMM connector population sequence
for memory mirrored channel mode.
| Number of installed microprocessor |
DIMM connector population sequence |
| One microprocessor installed |
6, 8-> 1, 3-> 5, 7-> 2, 4 |
| Two microprocessors installed |
6, 8-> 9, 11-> 1, 3-> 14, 16-> 5, 7-> 10, 12->
2, 4-> 13, 15 |