Owners Manual

Table 7. Memory channels
Process
or
Channel 0 Channel 1 Channel 2 Channel 3 Channel 4 Channel 5
Processo
r 1
Slots A1 and
A7
Slots A2 and A8 Slots A3 and A9 Slots A4 and A10 Slots A5 and A11 Slots A6 and A12
Processo
r 2
Slots B1 and
B7
Slots B2 and B8 Slots B3 and B9 Slots B4 and B10 Slots B5 and B11 Slots B6 and B12
Table 8. Memory population
Processor DIMM
type
DIMM
Ranking
Capacity Voltage Maximum Speed (1
DIMM per channel)
Maximum Speed (2
DIMM per channel)
SkyLake RDIMM 1R/2R 8 GB, 16 GB, 32
GB
1.2 V 2666 2666
RDIMM 4R/8R 64 GB, 128 GB 1.2 V 2666 2666
CascadeLake RDIMM 1R 8 GB 1.2 V 2666 2666
RDIMM 2R 16 GB, 32 Gb, 64
GB
1.2 V 2933 2666
LRDIMM 4R/8R 64 GB, 128 Gb 1.2 V 2666 2666
General memory module installation guidelines
To ensure optimal performance of your system, observe the following general guidelines when configuring your system memory.
If your system's memory configurations fail to observe these guidelines, your system might not boot, stop responding during
memory configuration, or operate with reduced memory.
The memory bus may operate at frequency can be 2933 MT/s, 2666 MT/s, 2400 MT/s, or 2133 MT/s depending on the
following factors:
● System profile selected (for example, Performance Optimized, or Custom [can be run at high speed or lower])
● Maximum supported DIMM speed of the processors. For memory frequency of 2933 MT/s, one DIMM per channel is
supported.
● Maximum supported DIMM speed of the processors.
● Maximum supported speed of the DIMMs
NOTE: MT/s indicates DIMM speed in MegaTransfers per second.
The system supports Flexible Memory Configuration, enabling the system to be configured and run in any valid chipset
architectural configuration. The following are the recommended guidelines for installing memory modules:
● All DIMMs must be DDR4.
● RDIMMs and LRDIMMs must not be mixed.
● x4 and x8 DRAM based memory modules can be mixed.
● Up to two RDIMMs can be populated per channel regardless of rank count.
● Up to two LRDIMMs can be populated per channel regardless of rank count.
● A maximum of two different ranked DIMMs can be populated in a channel regardless of rank count.
● If memory modules with different speeds are installed, they will operate at the speed of the slowest installed memory
module(s).
● Populate memory module sockets only if a processor is installed.
○ For dual-processor systems, sockets A1 to A12 and sockets B1 to B12 are available.
● Populate all the sockets with white release tabs first, followed by the black release tabs.
● When mixing memory modules with different capacities, populate the sockets with memory modules with the highest
capacity first.
For example, if you want to mix 8 GB and 16 GB memory modules, populate 16 GB memory modules in the sockets with white
release tabs and 8 GB memory modules in the sockets with black release tabs.
● Memory modules of different capacities can be mixed provided other memory population rules are followed.
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PowerEdge C4140 installing and removing system components