108 Installing System ComponentsMemory Mirroring SupportThe system supports memory mirroring if identical memory modules areinstalled in the two channels closest to the processor (memory should not beinstalled in the farthest channel). Mirroring must be enabled in the SystemSetup program. In a mirrored configuration, the total available system memoryis one-half of the total installed physical memory.Optimizer (Independent Channel) ModeIn this mode, all three channels are populated with identical memorymodules. This mode permits a larger total memory capacity but does notsupport SDDC with x8-based memory modules.A minimal single-channel configuration of one 1-GB memory module perprocessor is also supported in this mode.Table 3-1 and Table 3-2 show sample memory configurations that follow theappropriate memory guidelines stated in this section. The samples showidentical memory-module configurations and their the physical and availablememory totals. The tables do not show mixed or quad-rank memory-moduleconfigurations, nor do they address the memory speed considerations of anyconfiguration.Table 3-1. Sample RDIMM Single- and Dual-Rank Memory Configurations (PerProcessor)MemoryModeMemoryModuleSizeMemorySocketsSingle Processor Dual Processor4 1 2 3 PhysicalMemory(GB)AvailableMemory(GB)PhysicalMemory(GB)AvailableMemory(GB)Optimizer 1-GBXXXXXXXXXXXX12324all 24648all
