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Green 288-pin DDR4 RDIMM module with black chips, no heat spreader

OWC

OWC 16GB DDR4 2666 ECC Registered RDIMM D4RD-2666-16G RS18017xs+ server RAM

SKU CH-07MD-FT4XA

16GB DDR4 2666 ECC registered RDIMM for Synology RS18017xs+ servers, CL19 at 1.2V

  • Total capacity16 GB
  • Rated speedDDR4 2666 (PC4 21300)
  • CAS latencyCL19
  • Rated voltage1.2 V
  • Buffer typeRegistered
  • Memory rank2Rx4

Capacity 16GB

Rank 2Rx4

  • ECC registered design protects data integrity in servers
  • 16 GB capacity expands memory for demanding workloads
  • DDR4 2666 MHz speed matches system specifications
  • 2 V operation reduces power draw and heat
  • Backward compatible with 2133 MHz and 2400 MHz systems

Server-grade DDR4 ECC Registered DIMM

This 16GB DDR4 2666 MHz module is built for servers, workstations and compatible NAS systems that require registered ECC memory. It operates at 1.2V with CL19 latency and a 2Rx4 rank configuration on a 288-pin form factor. The part is designed as a direct upgrade for the Synology RackStation RS18017xs+ and matches OEM specifications.

Fits registered ECC memory slots only

The module must be installed in a platform that supports DDR4 registered ECC DIMMs; it will not work in standard desktop computers or alongside unbuffered or load-reduced ECC memory. Backward compatibility with 2133 MHz and 2400 MHz bus speeds allows it to slot into older DDR4 server boards without configuration changes. A single 16GB stick leaves remaining DIMM slots free for further capacity expansion.

JEDEC and RoHS compliant build

Full compliance with JEDEC standards and RoHS directives means the upgrade is warranty-safe for the host system. OWC validates every module in-house, providing a limited lifetime warranty with free technical support and an advanced replacement program. No heat spreader is included, ensuring clearance in dense server chassis.

How it compares

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

Price $109.99
Cheaper than about 66% of the 6,523 comparable items (median $188.99).
Total capacity 16 GB
Lower than about 60% of the 6,064 comparable items (median 32 GB).
Price per GB $6.87 per GB
Cheaper than about 54% of the 6,064 comparable items (median $7.25 per GB).

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Specifications

Product
Brand nameOWC
Part number2R6D42R416 GB
Total capacity16 GB
Product type288-Pin DDR4 SDRAM
Performance
Rated speedDDR4 2666 (PC4 21300)
Memory
CAS latencyCL19
ECC supportYes
Buffer typeRegistered
Memory rank2Rx4
Heat spreaderNo
Power
Rated voltage1.2 V

Other versions of this model

5 more in the same range

Questions about this item

How many registered DIMM slots must the Synology RS18017xs+ have free for this 16 GB module?

One free 288-pin DDR4 RDIMM slot is required; the module is a single 16 GB stick.

What power draw and heat output should I expect from this 1.2 V ECC registered DIMM under continuous load?

It runs at the standard DDR4 1.2 V with no heat spreader, so power draw and thermals stay within JEDEC limits for registered server memory.

Which memory types already installed in the RS18017xs+ would prevent this RDIMM from working?

It cannot be mixed with unbuffered or load-reduced ECC modules; only registered ECC DDR4 DIMMs are compatible.

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