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Two green DDR4 SODIMM sticks, 260-pin, no heat spreader

NEMIX RAM

NEMIX RAM 16GB (2x8GB) DDR4 2400 CL17 SODIMM memory upgrade for Apple iMac 2017 21.5

SKU CH-KNHY-13QZ4

16 GB DDR4 2400 CL17 SODIMM kit (2×8 GB) compatible with 2017 21.5-inch iMac

  • Total capacity16 GB (2 × 8 GB)
  • Rated speedDDR4 2400 (PC4 19200)
  • ChipsetMajor OEM Samsung, Micron, Hynix
  • CAS latencyCL17
  • Buffer typeUnbuffered
  • Rated voltage1.2 V
  • Boosts multitasking with 16 GB dual-channel DDR4 kit
  • Runs cool at 1.2 V for stable iMac operation
  • Tested compatible with 2017 21.5" Retina 4K & non-Retina
  • CL17 latency keeps everyday tasks responsive
  • 260-pin SODIMM fits straight into the memory slots

Apple iMac 2017 21.5 memory kit

This 16 GB kit contains two 8 GB DDR4 2400 SODIMM modules built for the Apple iMac 2017 21.5 inch Retina 4K and non-Retina models. It runs at 1.20 V with CL17 latency and uses unbuffered non-ECC chips from major OEM suppliers. The 260-pin form factor matches the factory SO-DIMM slots exactly.

DDR4 2400 SO-DIMM speed ceiling

The iMac 2017 21.5 inch memory controller is specified for DDR4 2400, so these modules operate at their rated 2400 MT/s without down-clocking. Faster DDR4 2666 parts will still work but will run at the lower 2400 ceiling. The dual-rank 1Rx8 organisation fits the platform's supported density per slot.

Check slot count and maximum capacity

Before ordering, verify how many SO-DIMM slots your specific iMac 2017 21.5 inch unit exposes and what total capacity the firmware accepts. Some configurations ship with soldered memory and only one upgrade slot, while others offer two user-accessible slots. The Apple service manual for your exact model number states the supported maximum.

How it compares

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

Price $80.99
Cheaper than about 70% of the 21,161 comparable items (median $397.99).
Total capacity 16 GB (2 × 8 GB)
Lower than about 70% of the 20,941 comparable items (median 32 GB).
Price per GB $5.06 per GB
Cheaper than about 76% of the 20,941 comparable items (median $8.19 per GB).

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Specifications

Product
Brand nameNEMIX RAM
Product lineApple iMac/Mac Mini Compatible Series Memory
Model nameApple DDR4 2666 MHz ECC Unbuffered SODIMM
Part numberMS19200-818K2
Total capacity16 GB (2 × 8 GB)
Product type260-PIN DDR4 SODIMM
Performance
Rated speedDDR4 2400 (PC4 19200)
Processor
ChipsetMajor OEM Samsung, Micron, Hynix
Memory
CAS latencyCL17
ECC supportNo
Buffer typeUnbuffered
Heat spreaderNo
Memory rank1Rx8
Power
Rated voltage1.2 V
Compatibility
Compatible systemsApple
In the box
Included items16 GB (2 × 8 GB) DDR4 2400 MHz PC4-19200 2Rx8 1.2 V CL17 260-PIN Non-ECC Unbuffered SODIMM KIT

Questions about this item

Should I pick the 16GB kit or a single 8GB module for my 2017 iMac 21.5?

The 16GB kit provides two matched 8GB sticks for dual-channel bandwidth, which the iMac 21.5 2017 architecture benefits from. A single module would run in single-channel mode and halve memory throughput.

What does the 2400MHz rating deliver in an actual 2017 iMac 21.5?

The modules run at DDR4-2400 CL17 with 1.2V. The 2017 iMac 21.5 memory controller tops out at 2400MT/s, so you get the full rated speed and latency without down-clocking.

Is the 260-pin SODIMM interface the limiting factor for this upgrade?

The 260-pin DDR4 SODIMM form factor is the correct physical and electrical interface for the 2017 iMac 21.5. It supports the kit's PC4-19200 bandwidth and CL17 timing without any adapter or converter.

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