Dell PowerEdge R415 - Manual (Page 122)

122 Installing System Components
General Memory Module Installation Guidelines
To ensure optimal performance of your system, observe the following general
guidelines when configuring your system memory.
NOTE: Memory configurations that fail to observe these guidelines can prevent
your system from starting and producing any video output.
• RDIMMs and UDIMMs cannot be mixed.
• Except for memory channels that are unused, all populated memory
channels must have identical configurations.
• In a dual-processor configuration, the memory configuration for each
processor must be identical.
• Memory modules of different sizes can be mixed in A1–A4 or B1–B4
(for example, 2 GB and 4 GB), but all populated channels must have
identical configurations.
• For Optimizer Mode, memory modules are installed in the numeric order
of the sockets beginning with A1 or B1.
• 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).
Table 3-2, Table 3-3, and Table 3-4 show sample memory configurations that
follow the appropriate memory guidelines stated in this section.
The samples show identical memory-module configurations and the physical
and available memory totals. The tables do not show mixed or quad-rank
memory-module configurations, nor do they address the memory speed
considerations of any configuration.
R415HOM.book Page 122 Friday, September 24, 2010 9:37 AM