Dell PowerEdge M420 Hardware Owner's Manual - Page 166

Non-Optimal Memory Configurations System performance can be affected if your memory configuration does not conform to the preceding installation guidelines. Your system may issue an error message during start-up stating that your memory configuration is nonoptimal. Memory Sparing Support - PowerEdge M905 Memory sparing (spare bank) is supported in systems that have one of the memory configurations shown in Table 3-4. The memory sparing feature must also be enabled in the Memory Information screen of the System Setup program. See "Memory Settings Screen" on page 130. To use memory sparing, you must disable node interleaving. Table 3-4. Memory Sparing Configurations - PowerEdge M905 Total System Memory 48 GB 96 GB 192 GB Usable System Memory 40 GB 80 GB 160 GB Memory Modules Number and Size Twenty-four 2 GB Twenty-four 4 GB Twenty-four 8 GB Memory Module Locations A1, A2, A3, A4, A5, A6, A7, A8, B1, B2, B3, B4, B5, B6, B7, B8, C1, C2, C3, C4, D1, D2, D3, D4 System Memory - PowerEdge M805 You can upgrade your system memory to a maximum of 128 GB by installing 667 MHz registered DDR2 memory modules in sets of 1 GB, 2 GB, 4 GB, or 8 GB memory modules. (Dual-rank 8 GB modules are supported; quad-rank 8 GB modules are not supported.) Each processor has four memory channels, organized in sets of two channels. NOTE: If more than four memory modules are installed per processor, the memory modules are downclocked to operate at 533 MHz. 166 Installing Blade Components