Hardware Owner's Manual

184 Installing Blade Components
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 non-
optimal.
Memory Sparing Support – PowerEdge M905
Memory sparing (spare bank) is supported in systems that have one of the
memory configurations shown in Table 3-5.
The memory sparing feature must
also be enabled in the Memory Information screen of the System Setup
program. See "Memory Settings Screen
" on page 140 . To use memory sparing,
you must disable node interleaving.
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.
Table 3-5. Memory Sparing Configurations
– PowerEdge M905
NOTE: Memory sparing is supported if 24 identical memory modules are installed.
Total
System
Memory
Usable
System
Memory
Memory Modules -
Number and Size
Memory Module Locations
48 GB 40 GB Twenty-four 2 GB A1, A2, A3, A4, A5, A6, A7, A8, B1, B2,
B3, B4, B5, B6, B7, B8, C1, C2, C3, C4,
D1, D2, D3, D4
96 GB 80 GB Twenty-four 4 GB
192 GB 160 GB Twenty-four 8 GB