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Green DDR4 RDIMM module with black chips and gold contacts

A-Tech

A-Tech 4GB DDR4 2666MHz ECC RDIMM 1Rx8 Server Memory

SKU CH-G3AY-9AFKQ

4GB DDR4 2666MHz ECC RDIMM with CL19 latency, 1.20V operation, and 1Rx8 registered design for server and workstation upgrades

  • Total capacity4 GB
  • Rated speedDDR4 2666 (PC4 21300)
  • ChipsetMajor Brand Chipset
  • CAS latencyCL19
  • Rated voltage1.2 V
  • Buffer typeRegistered
  • 4GB DDR4 capacity expands server memory for heavier workloads
  • 2666MHz speed with CL19 latency accelerates data throughput for responsive operation
  • ECC registered design detects and corrects single-bit errors to protect data integrity
  • 2V standard voltage reduces power draw and heat in dense configurations
  • 288-pin DDR4 DIMM form factor fits compatible server and workstation slots

Server Memory Upgrade

This 4GB DDR4 2666MHz ECC RDIMM module targets administrators maintaining servers or workstations that require registered error-correcting memory. The single-rank 1Rx8 design operates at the standard 1.20V and fits 288-pin DIMM slots.

Replaces Crucial CT4G4RFS8266

The module is a compatible replacement for the Crucial CT4G4RFS8266 part number, matching its DDR4 2666 PC4-21300 speed and CL19 latency. The upgrade is worthwhile when a system reports correctable memory errors or when capacity limits prevent additional virtual machines from starting.

Sustained Load Behaviour

Registered buffering reduces electrical load on the memory controller, allowing stable operation during extended compute tasks. ECC circuitry corrects single-bit errors on the fly, preventing data corruption that can accumulate during long-running database or virtualisation workloads.

How it compares

Measured against everything we stock in ECC Server RAM, at today’s prices. Recalculated every night.

Price $18.99
Cheaper than about 95% of the 6,523 comparable items (median $188.99).
Total capacity 4 GB
Lower than about 95% of the 6,064 comparable items (median 32 GB).
Price per GB $4.75 per GB
Cheaper than about 75% of the 6,064 comparable items (median $7.25 per GB).

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Specifications

Product
Brand nameA-Tech
Product lineCompatible Replacement for Crucial
Model nameCT4G4RFS8266
Total capacity4 GB
Performance
Rated speedDDR4 2666 (PC4 21300)
Processor
ChipsetMajor Brand Chipset
Memory
CAS latencyCL19
ECC supportYes
Buffer typeRegistered
Memory rank1Rx8
Power
Rated voltage1.2 V

Questions about this item

Will this 288-pin DDR4 DIMM fit a standard server DIMM slot?

The module uses a 288-pin DDR4 DIMM form factor that matches standard server DIMM slots.

Do I need to install this registered ECC module in matched pairs for it to work?

Each 1Rx8 registered ECC module operates independently; matched pairs are not required for basic operation.

Will the 1.20V operating voltage match my server's DDR4 power rail?

The module runs at the standard DDR4 voltage of 1.20V, which is the default for all DDR4 server platforms.

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