Dell PowerEdge T610 Hardware Owner's Manual - Page 125

• Two memory modules per channel are limited to 800 MHz, regardless of memory module speed. • If quad-rank memory modules are mixed with single- or dual-rank modules, the quad-rank modules must be installed in the sockets with the white release levers. • If memory modules with different speeds are installed, they will operate at the speed of the slowest installed memory module(s). Mode-Specific Guidelines Three memory channels are allocated to each processor. The number of channels and allowable configurations depend on the memory mode selected. Advanced ECC (Lockstep) Mode Support In this configuration, the two channels closest to the processor are combined to form one 128-bit channel. This mode supports SDDC for both x4- and x8based memory modules. Memory modules must be identical in size, speed, and technology in corresponding slots. Memory Mirroring Support The system supports memory mirroring if identical memory modules are installed in the two channels closest to the processor (memory should not be installed in the farthest channel). Mirroring must be enabled in the System Setup program. In a mirrored configuration, the total available system memory is one-half of the total installed physical memory. Optimizer (Independent Channel) Mode In this mode, all three channels are populated with identical memory modules. This mode permits a larger total memory capacity but does not support SDDC with x8-based memory modules. A minimal single-channel configuration of one 1-GB memory module per processor is also supported in this mode. Table 3-2 and Table 3-3 show sample memory configurations that follow the appropriate memory guidelines stated in this section. The samples show identical memory-module configurations and their the physical and available Installing System Components 125