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Four green DDR4 RDIMM modules, no heat spreaders

NEMIX RAM

NEMIX RAM 128GB (4×32GB) DDR4 2666 ECC RDIMM memory upgrade

SKU CH-CFHV-GS4XS

128GB quad-channel DDR4-2666 ECC registered kit validated for Synology SA3400 NAS

  • Total capacity128 GB (4 × 32 GB)
  • Rated speedDDR4 2666 (PC4 21300)
  • ChipsetMajor OEM Samsung, Micron, Hynix
  • CAS latencyCL19
  • Buffer typeRegistered
  • Rated voltage1.2 V
  • 128 GB total capacity expands Synology SA3400 NAS headroom
  • Four 32 GB DDR4 2666 modules deliver 21300 MT/s throughput
  • ECC registered RDIMM design protects data integrity under load
  • 2 V operation reduces power draw in 24/7 environments
  • 288-pin 2Rx4 layout ensures direct compatibility with SA3400 platform

Synology SA3400 NAS memory upgrade

This 128 GB kit contains four 32 GB DDR4 2666 ECC registered DIMMs built for the Synology SA3400 NAS. It targets administrators who need to maximise the memory slots in that specific platform. The modules operate at 1.2 V with CL19 latency and use major OEM chips from Samsung, Micron or Hynix.

Registered ECC RDIMM requirement

The single specification that decides fit is the registered ECC RDIMM format; the SA3400 only accepts buffered modules with error correction. Unbuffered or non-ECC DIMMs will not function in this system. Each stick is a 288-pin DDR4 RDIMM organised as 2Rx4, matching the motherboard's electrical and mechanical requirements exactly.

128 GB capacity for virtualisation workloads

Four ranks per channel provide 128 GB total, giving comfortable headroom for multiple virtual machines, Docker containers and large file-system caches on the SA3400. The kit fills all available slots, so further expansion would require replacing modules rather than adding them. Performance scales with the platform's 2666 MT/s limit; workloads needing higher bandwidth or lower latency will hit the memory controller ceiling.

How it compares

Measured against everything we stock in Model-Specific Memory Upgrades, at today’s prices. Recalculated every night.

Price $843.99
Pricier than about 59% of the 21,161 comparable items (median $397.99).
Total capacity 128 GB (4 × 32 GB)
Higher than about 70% of the 20,941 comparable items (median 32 GB).
Price per GB $6.59 per GB
Cheaper than about 60% of the 20,941 comparable items (median $8.19 per GB).

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Specifications

Product
Brand nameNEMIX RAM
Product lineSynology Compatible Series NAS Memory
Model nameSynology DDR4 2666 MHz ECC RDIMM Registered Server Memory
Part numberMR21300-324K4
Total capacity128 GB (4 × 32 GB)
Product type288-Pin DDR4 RDIMM
Performance
Rated speedDDR4 2666 (PC4 21300)
Processor
ChipsetMajor OEM Samsung, Micron, Hynix
Memory
CAS latencyCL19
ECC supportYes
Buffer typeRegistered
Heat spreaderNo
Memory rank2Rx4
Power
Rated voltage1.2 V
Compatibility
Compatible systemsSynology
In the box
Included items128 GB (4 × 32 GB) DDR4 2666 MHz PC4-21300 2Rx4 1.2 V CL19 288-PIN ECC RDIMM Registered Server Memory KIT

Questions about this item

What does the 2666 MHz speed mean for my Synology SA3400 NAS performance?

The 2666 MHz rating sets the maximum data rate the modules can sustain, so your SA3400 will run the memory at its supported DDR4 2666 speed for consistent throughput.

How does the ECC RDIMM registered design affect compatibility with the SA3400?

The registered ECC RDIMM format matches the SA3400's server memory architecture, providing error correction and signal buffering required for stable operation.

Will the 288-pin DDR4 modules fit the SA3400 memory slots without a heat spreader?

Yes, the 288-pin DDR4 RDIMM form factor fits the SA3400 DIMM slots directly; the modules have no heat spreader, so they install in the standard low-profile bays.

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