System memory, General memory module installation guidelines, General memory module installation – Dell PowerEdge R715 User Manual
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Installing System Components
System Memory
Your system supports ECC DDR3 registered DIMMs (RDIMMs) and
unbuffered registered DIMMs (UDIMMs). Single-, dual- and quad-rank
DIMMs of speeds up to 1333 MHz (1066 MHz for quad rank) are supported.
RDIMMs of capacities 1 GB, 2 GB, 4 GB, 8 GB, and 16 GB are supported for
a total of up to 256 GB. 1 GB and 2 GB UDIMMs are supported.
The system consists of 16 memory sockets split into two sets of eight sockets;
one set for each processor. Each eight-memory socket set is further organized
into four DDR3 memory channels. The first socket of each DDR3 memory
channel is marked with a white release lever.
Each channel supports up to two single-, dual- or quad-rank RDIMMs or up
to two UDIMMs.
The following features are available with respect to memory:
• Each processor has four DDR3 channels that support speeds up to 1333 MHz.
• UDIMMs and RDIMMs cannot be mixed.
• Your system may support online memory sparing.
• Up to 256 GB of memory (with 16 x 16 GB RDIMMs).
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.
• DIMMs must be populated in matched set of four or two DIMMs for each
processor (for example, A1/A2, A3/A4). Single DIMM operation is not
supported.
• All processor memory channels must be populated identically
(same speed, size, and type).
• Mixing of memory sizes and ranks is allowed for flexibility.
• The memory configuration for each processor must be identical for
optimal performance.
• Always start memory population at x1, where x is A or B. Sockets A and B
correspond to processors 1 and 2 respectively.
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