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Memory modes
The server supports several memory features that allow flexibility in
performance, redundancy, and ability to upgrade. The system BIOS can
be configured as follows:
• Maximum compatibility
• Maximum performance
•Memory sparing
• Memory RAID
• Memory mirroring
Only one of these memory modes can be selected at one time and the
BIOS defaults to maximum performance mode. For non-redundant
modes, support is also included for memory sparing, where a portion
of each memory board is reserved for failover.
The table below lists the memory hot-plug support under different
memory modes.
Memory boards configured using RAID or mirroring are in redundant
mode. If a memory board that is configured in a redundant mode has a
DIMM or memory board fault, the memory board and/or DIMM
containing the fault can be hot-removed or hot-replaced while the
system is powered on.
Hot-replace means you can replace a memory board with another
memory board of identical size. This operation is supported in memory
RAID and memory mirroring modes.
Hot-add means you can add a memory board to a previously
unoccuppied slot. This requires OS support and is supported in
maximum compatibility and memory mirroring modes.
Hot-upgrade means you can replace an existing memory board with a
memory board that contains more memory capacity. This requires OS
support and is supported by the memory RAID mode only.
Memory
Hot-plug
Operation
Maximum
Compatibility
Maximum
Performance
Memory
Mirroring
Memory
RAID
Hot-add Supported Supported
Hot-replace Supported Supported
Hot-upgrade Supported