Dell PowerEdge M420 Hardware Owner's Manual - Page 182

• In a dual-processor configuration, the memory configuration for each processor must be identical • If quad-rank memory modules are installed, a maximum of two DIMMs per channel is supported. • If memory modules with different speeds are installed, they operate at the speed of the slowest installed memory modules. Three memory channels are allocated to each processor. The number of channels used and the allowable configurations depend on the memory mode selected. The channels are organized as follows: • Channel 0 - sockets 3, 6 • Channel 1 - sockets 2, 5 • Channel 2 - sockets 1, 4 Sockets A1 through A6 are assigned to CPU1; sockets B1 through B6 are assigned to CPU2. Advanced ECC Mode Support - PowerEdge M610/M610x In this configuration, channels 0 and 1 are combined to form one 128-bit channel. If a memory error occurs on a given chip, the faulty chip is disabled. Memory modules must be identical in size, speed, and technology in corresponding slots. Memory Mirroring Support - PowerEdge M610/M610x The system supports memory mirroring if identical memory modules are installed in channel 0 and channel 1 (memory is not installed in channel 2). Mirroring must also 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. 182 Installing Blade Components