Dell EMC PowerEdge MX740c User Manual

Table 7. Memory population
DIMM Type DIMM Ranking Capacity Voltage Operating Frequency (in MT/s)
RDIMM 1R / 2R 8 GB, 16 GB, 32 GB 1.2 V 2666
LRDIMM 4R / 8R 64 GB, 128 GB 1.2 V 2666
General memory module installation guidelines
To ensure optimal performance of your system, observe the following general guidelines when conguring your system memory. If your
system's memory congurations fail to observe these guidelines, your system might not boot, stop responding during memory
conguration, or operate with reduced memory.
The memory bus may operate at frequency can be 2666 MT/s, 2400 MT/s, or 2133 MT/s depending on the following factors:
• System prole selected (for example, Performance Optimized, or Custom [can be run at high speed or lower])
• 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 Conguration, enabling the system to be congured and run in any valid chipset architectural
conguration. The following are the recommended guidelines for installing memory modules:
• All DIMMs must be DDR4.
• RDIMMs and LRDIMMs must not be mixed.
• 64 GB LRDIMMs that are DDP (Dual Die Package) LRDIMMs must not be mixed with 128 GB LRDIMMs that are TSV (Through Silicon
Via/3DS) LRDIMMs.
• 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 dierent ranked DIMMs can be populated in a channel regardless of rank count.
• If memory modules with dierent 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 single-processor systems, sockets A1 to A12 are available.
– For dual-processor systems, sockets A1 to A12 and sockets B1 to B12 are available.
• Populate all the sockets with white release tabs rst, followed by the black release tabs.
• When mixing memory modules with dierent capacities, populate the sockets with memory modules with the highest capacity rst.
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 dierent capacities can be mixed provided other memory population rules are followed.
For example, 8 GB and 16 GB memory modules can be mixed.
• In a dual-processor conguration, the memory conguration for each processor must be identical.
For example, if you populate socket A1 for processor 1, then populate socket B1 for processor 2, and so on.
• Mixing of more than two memory module capacities in a system is not supported.
• Unbalanced memory congurations will result in a performance loss so always populate memory channels identically with identical
DIMMs for best performance.
• Populate six identical memory modules per processor (one DIMM per channel) at a time to maximize performance.
• To ensure proper system cooling, memory module blanks must be installed in memory sockets that are not occupied.
DIMM population update for Performance Optimized mode with quantity of 4 and 8 DIMMs per processor.
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Installing and removing system components

Dell EMC PowerEdge MX740c Specifications

General

Brand	Dell EMC
Model	PowerEdge MX740c
Category	Server
Language	English