Dell PowerEdge R715 - Manual (Page 93)

Installing System Components 93
• In case of mixed-rank population, first populate the DIMM with the
highest number of ranks (in sockets with white release levers).
• If memory modules with different speeds are installed, they operate at the
speed of the slowest installed memory module(s).
• If online sparing is enabled, identical DIMMs must be installed in the
same slots across each channel.
The system supports advanced ECC, memory interleaving, and online
sparing. For information on memory configurations, see Table 3-2.
Memory Sparing Support
Memory sparing is supported in systems that have one of the fully populated
memory configurations shown in Table 3-2. The memory sparing feature
must be enabled in the Memory Settings screen of the System Setup
program. See "Using the System Setup Program and UEFI Boot Manager" on
page 55.
NOTE: The memory sparing and node interleaving features cannot be used at the
same time. To use memory sparing, you must disable the Node Interleaving option
in the System Setup program.
To support memory sparing, all eight DIMM sockets of each CPU must be
populated. When enabled, memory sparing allocates and reserves one rank of
memory from the installed DIMMs and is large enough to act as spare
memory in the event of a memory rank failure where the contents of the
failed rank is copied to the spared rank.
book.book Page 93 Thursday, June 3, 2010 4:35 PM