Intel S5500BC, User Manual

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Intel
®
Server Board S5500BC User’s Guide 11
Figure 6. Channel Slots Configuration
The Independent Channel Mode is the default Maximum Performance Mode preferred for
Intel
®
Xeon
®
5500 processor series based platforms. You can populate all three channels
in any order and have no matching requirements. All channels must run at the same
interface frequency, but individual channels may run at different DIMM timings (RAS
latency, CAS latency, and so forth).
Memory Sparing and Mirroring
The spare mode is not supported by the Intel
®
Server Board S5500BC.
With memory mirroring, the system maintains two copies of all data in the memory
subsystem. If a DIMM fails, the data is not lost because the second copy of the data is
available from the mirrored DIMM in the opposite channel. The system will not fail due
to memory error unless both the primary and the mirrored copy of the data become corrupt
at the same time.
In a mirrored system, the maximum usable memory is one-half of the installed memory
with a minimum of two DIMMs installed. Since the data is duplicated across DIMMs, it
means that up to one-half of the installed DIMMs are actively in use at any one time. The
remaining DIMMs are used for mirroring.