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Green circuit board with black memory chips and gold edge connector

Crucial

Crucial CT16G4S266M 16GB DDR4 2666 SO-DIMM memory upgrade

SKU CH-J14G-5H8NQ MPN CT16G4S266M

16 GB DDR4 SO-DIMM tested for the 2019 27-inch iMac Retina 5K at 2666 MHz

  • Type260-Pin DDR4 SO-DIMM
  • CompatibilityFor Apple iMac
  • Capacity16GB
  • SpeedDDR4 2666 (PC4 21300)
  • CAS Latency19
  • Voltage1.2V
  • Boosts iMac responsiveness with 16 GB DDR4 2666 memory
  • Low 1.2 V operation reduces system power draw
  • CAS latency 19 delivers snappy data access
  • Validated for 27-inch 2019 iMac Retina 5K models
  • Rigorous component-level testing ensures reliable operation

16 GB DDR4 SO-DIMM for 2019 iMac

This 16 GB DDR4 2666 SO-DIMM is built for the Apple iMac Retina 5K, 27-inch, 2019 models with 3.0 GHz or 3.4 GHz Intel Core i5 processors. The 260-pin unbuffered module runs at 1.2 V with CAS latency 19. Every unit is tested at component and module level before shipping.

Suits owners of the specified 2019 iMac

It fits the iMac 19,1 platform and installs without special tools. Builders working on Windows laptops, earlier Macs, or any system that requires ECC or registered memory should look elsewhere. The module is non-ECC and unbuffered, so it will not meet server or workstation requirements.

260-pin DDR4 2666 SO-DIMM form factor

The 260-pin DDR4 SO-DIMM interface is the single specification that decides compatibility. Only systems designed for this exact pin count, voltage, and speed will accept the module. Verify your model matches the 2019 27-inch iMac before purchase.

Highlights

  • Boosts iMac responsiveness with 16 GB DDR4 2666 memory
  • Low 1.2 V operation reduces system power draw
  • CAS latency 19 delivers snappy data access
  • Validated for 27-inch 2019 iMac Retina 5K models
  • Rigorous component-level testing ensures reliable operation

Specifications

BrandCrucial
ModelCT16G4S266M
Type260-Pin DDR4 SO-DIMM
CompatibilityFor Apple iMac
Capacity16GB
SpeedDDR4 2666 (PC4 21300)
CAS Latency19
Voltage1.2V
ECCNo
Buffered/RegisteredUnbuffered
FeaturesIncreases Mac system performance
Compatible with the Apple iMac Retina 5K, 27-inch, 2019 Intel Core i5, 3.0 GHz & 3.4 GHz models
Every single module extensively tested at the component and module level
Easy to install
Shipping weight0.02 kg
Package size99 × 50 × 3 mm

Questions about this item

How much power does the 1.2V DDR4 module draw when the iMac runs all day?

The module operates at the standard DDR4 voltage of 1.2V, which keeps power draw low during continuous use.

Which slot type must my iMac have for this 260-pin SO-DIMM to fit?

Your iMac needs a DDR4 SO-DIMM slot accepting 260-pin modules; the 2019 27-inch Retina 5K iMac uses this format.

Will the CL19 2666MHz module run at its rated speed in my 2019 iMac with a 3.0 GHz Core i5?

Yes, the 2019 27-inch iMac with 3.0 GHz or 3.4 GHz Core i5 supports DDR4 2666, so the module runs at its full 2666 MT/s rating.

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