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Green circuit board DDR4 RDIMM module with black chips, 288 gold pins, no heat spreader

A-Tech

A-Tech 4GB DDR4 2666MHz ECC RDIMM 288-Pin Memory Upgrade

SKU CH-6R94-6Y9T6

4GB DDR4 2666MHz ECC registered RDIMM for late-2017 iMac Pro 27-inch Retina 5K

  • Total capacity4 GB
  • Rated speedDDR4 2666 (PC4 21300)
  • ChipsetMajor Brand Chipset
  • Rated voltage1.2 V
  • Buffer typeRegistered
  • Memory rank1Rx8
  • 4GB capacity expands multitasking headroom on iMac Pro
  • DDR4 2666MHz PC4-21300 speed accelerates data throughput
  • ECC registered design protects data integrity under load
  • 288-pin RDIMM form factor fits Late 2017 iMac Pro
  • 20V operation reduces power draw and heat

System-Specific Mac Upgrade

This 4 GB DDR4 module is built for the Apple iMac Pro (Retina 5K, 27-inch, Late 2017). It matches the factory memory specification for model identifiers iMacPro1,1 and A1862 (EMC 3144). The registered ECC design meets the workstation-class requirements of that platform.

Sustained Workload Behaviour

Registered buffering and ECC correction keep data integrity stable during long rendering or compute sessions. The 1.20 V operating voltage maintains consistent power draw without thermal throttling under continuous load. Single-rank 1Rx8 organisation allows the memory controller to sustain bandwidth across all populated slots.

Compatibility Decider

This part fits only systems that accept DDR4 2666/2667 MHz (PC4-21300) ECC RDIMM 288-pin modules. It will not work in consumer iMac models, MacBook Pro units, or any platform that requires unbuffered non-ECC SODIMMs.

How it compares

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

Price $17.99
Cheaper than about 92% of the 21,161 comparable items (median $397.99).
Total capacity 4 GB
Lower than about 90% of the 20,941 comparable items (median 32 GB).
Price per GB $4.50 per GB
Cheaper than about 81% of the 20,941 comparable items (median $8.19 per GB).

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Specifications

Product
Brand nameA-Tech
Product lineA-Tech DDR4 Apple Mac RAM Memory Upgrades
Total capacity4 GB
Performance
Rated speedDDR4 2666 (PC4 21300)
Processor
ChipsetMajor Brand Chipset
Memory
ECC supportYes
Buffer typeRegistered
Memory rank1Rx8
Heat spreaderNo
Power
Rated voltage1.2 V
Compatibility
Compatible systemsApple Mac Systems

Questions about this item

How much power does the 1.20V DDR4 2666MHz ECC RDIMM draw during continuous operation?

The module runs at 1.20 volts, the standard DDR4 operating voltage, keeping power draw low even under sustained workloads.

Does my iMac Pro (Late 2017) need any specific firmware or macOS version to recognise this 288-pin RDIMM?

The memory is certified for iMacPro1,1 (model A1862, EMC 3144) and works with the firmware shipped on those systems.

Can I mix this 4GB 1Rx8 registered ECC module with the original Apple memory already installed?

Yes, it is designed to operate alongside the factory-installed DDR4 2666/2667 MHz ECC RDIMMs in the same iMac Pro.

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