IBM Redboks System x3550 M4, Инструкция по установке и эксплуатации

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v
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.
v
The maximum available memory is reduced to half of the installed memory when
memory mirrored channel is enabled. For example, if you install 64 GB of
memory using RDIMMs, only 32 GB of addressable memory is available when
you use memory mirrored channel.
v For UDIMMs, DIMM connectors 3, 6, 7, and 10 for microprocessor 1 and DIMM
connectors 15, 18, 19, and 22 for microprocessor 2 are not used in memory
mirrored channel mode.
The following diagram lists the DIMM connectors on each memory channel.
The following table shows the installation sequence for memory mirrored channel
mode:
Table 8. Memory mirrored channel mode DIMM population sequence
Number of DIMMs
Number of installed
microprocessor
DIMM connector
First pair of DIMMs 1 1, 4
Second pair of DIMMs 1 9, 12
Third pair of DIMMs 1 2, 5
Fourth pair of DIMMs 1 8, 11
Fifth pair of DIMMs 1 3, 6
Sixth pair of DIMMs 1 7, 10
Seventh pair of DIMMs 2 13, 16
Eighth pair of DIMMs 2 21, 24
Ninth pair of DIMMs 2 14, 17
Tenth pair of DIMMs 2 20, 23
Eleventh pair of DIMMs 2 15, 18
Twelfth pair of DIMMs 2 19, 22
Note: DIMM connectors 3, 6, 7, 10, 15, 18, 19, and 22 are not used in memory mirrored
channel mode when UDIMMs are installed in the server.
Memory rank sparing
The memory rank sparing feature disables the failed memory from the system
configuration and activates a rank sparing DIMM to replace the failed active DIMM.
You can enable either rank sparing memory or memory mirrored channel in the
Setup utility (see “Starting the Setup utility” on page 109). When you use the
memory rank sparing feature, consider the following information:
Figure 1. Connectors on each memory channel
Chapter 2. Installing optional devices
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