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NEMIX RAM

NEMIX RAM 16GB (2x8GB) DDR4 2666MHz ECC SODIMM Kit for Synology DS1821+

SKU CH-BQNC-8M3D2

16 GB kit of two 8 GB DDR4 ECC SODIMMs at 2666 MHz for Synology DS1821+ NAS

  • Total capacity16 GB (2 × 8 GB)
  • Rated speedDDR4 2666 (PC4 21300)
  • ChipsetMajor OEM Samsung, Micron, Hynix
  • CAS latencyCL19
  • Buffer typeUnbuffered
  • Rated voltage1.2 V
  • ECC protection guards data integrity
  • DDR4 2666 speed matches NAS spec
  • Dual 8 GB modules give 16 GB total
  • 2 V operation keeps power draw low
  • 260-pin SODIMM fits DS1821+ slots

Synology DS1821+ DDR4 ECC SODIMM Kit

This 16 GB kit contains two 8 GB unbuffered DDR4 2666 ECC SODIMMs built for the Synology DS1821+ NAS. It targets administrators who need to expand memory capacity while keeping data-integrity protection. The modules use 1Rx8 organisation and run at 1.2 V without heat spreaders.

ECC Unbuffered DDR4 2666 with 1Rx8 Rank

The single specification that decides fit is the ECC unbuffered DDR4 2666 1Rx8 configuration at CL19 latency. Synology DS1821+ requires exactly this combination; registered or non-ECC modules will not work. The 260-pin form factor and PC4-21300 rating match the platform's memory controller requirements.

Tool-Less Slot Access With Firm Seating Check

Installation uses the NAS's tool-less side cover and two SODIMM slots; modules click in vertically. The most common issue is incomplete seating — press each stick until both retention clips snap audibly. Verify the new capacity appears in DSM before closing the chassis.

How it compares

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

Price $114.99
Cheaper than about 66% 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 $7.19 per GB
Cheaper than about 56% 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 Unbuffered SODIMM
Part numberMSE21300-818K2
Total capacity16 GB (2 × 8 GB)
Product type260-PIN DDR4 ECC SODIMM
Performance
Rated speedDDR4 2666 (PC4 21300)
Processor
ChipsetMajor OEM Samsung, Micron, Hynix
Memory
CAS latencyCL19
ECC supportYes
Buffer typeUnbuffered
Heat spreaderNo
Memory rank1Rx8
Power
Rated voltage1.2 V
Compatibility
Compatible systemsSynology
In the box
Included items16 GB (2 × 8 GB) DDR4 2666 MHz PC4-21300 1Rx8 1.2 V CL19 260-PIN ECC Unbuffered SODIMM KIT

Questions about this item

What does the 2666MHz speed mean once installed in my DS1821+?

The modules run at DDR4 2666 (PC4-21300) with CL19 latency, matching the NAS memory controller so the system operates at its rated throughput without downclocking.

How does the 260-pin ECC SODIMM interface affect compatibility?

The 260-pin DDR4 ECC unbuffered SODIMM form factor is the exact slot type used by the DS1821+, and the on-module ECC provides single-bit error correction for data integrity.

Will the two 8GB sticks fit the DS1821+ memory slots without a heat spreader?

Yes, the low-profile design has no heat spreader, so both 260-pin modules seat cleanly in the NAS memory bays without clearance issues.

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