A-Tech
256GB Kit (2x128GB) DDR4 2666MHz PC4-21300 ECC RDIMM 8Rx4 (3DS 2S4Rx4) Octal Rank 1.2V ECC Registered DIMM 288-Pin Server & Workstation RAM Memory Upgrade Modules (A-Tech Enterprise Series)
*Price sourced from Amazon.com. Last updated 2026-07-22. Price and availability subject to change.
Bottom line: The 256GB Kit (2x128GB) DDR4 2666MHz PC4-21300 ECC RDIMM 8Rx4 (3DS 2S4Rx4) Octal Rank 1.2V ECC Registered DIMM 288-Pin Server & Workstation RAM Memory Upgrade Modules (A-Tech Enterprise Series) is a niche pick — read recent reviews before buying in the memory & ram category, priced around $1671.98. Read recent reviews carefully before committing.
SpecPicks Verdict
SpecPicks classifies A-Tech 256GB Kit (2x128GB) DDR4 2666MHz PC4-21300 ECC RDIMM 8Rx4… as a niche pick — read recent reviews before buying in the memory & ram category, based on our editorial and benchmark analysis and our ranking model that weights rating × review-volume × price-fit. A-Tech's positioning sits within the broader category mid-tier. Use the Compare tool to put it side-by-side with two or three close alternatives before clicking through to Amazon.
Common buyer scenarios for memory & ram of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the Amazon listing before purchase. Prices, stock, and Prime eligibility update directly from Amazon's catalog and may have moved since this page was last verified.
Pros & Cons
Pros
- ✓ ECC Registered RDIMM; 8Rx4 (3DS 2S4Rx4) - Octal Rank x4; JEDEC DDR4 standard 1.2V
- ✓ Backed by A-Tech's warranty and support channels
- ✓ Ships via Amazon with Prime eligibility and the standard returns policy
Cons
- ✗ Confirm socket / form-factor / power-rating compatibility against your build before ordering
- ✗ Price, stock, and Prime eligibility update from Amazon and may have changed since this page was last verified
Key Features
- A-Tech RAM Memory compatible for select DDR4 Servers & Workstation systems only; (*WILL NOT WORK with Desktop Computers, Laptop Computers, or PCs of any kind*)
- 256GB RAM Kit (2 x 128GB Modules); DDR4 DIMM 288 Pin; Speeds up to 2666MHz/2667MHz PC4-21300 (PC4-2666V)
- ECC Registered RDIMM; 8Rx4 (3DS 2S4Rx4) - Octal Rank x4; JEDEC DDR4 standard 1.2V
- Improves system performance, workload capacity, and reduces bottlenecks by increasing memory (RAM) resources
- Note: This memory is ECC Registered and cannot be mixed with different ECC types such as ECC Unbuffered, ECC Load Reduced, or Non-ECC Unbuffered; (Memory compatibility can vary among different system models and their installed components; please verify compatibility and follow memory channel guidelines to ensure maximum performance)
- Each A-Tech memory module is built and tested for superior performance and trusted reliability
Full Specifications
| Brand | A-Tech |
|---|---|
| Voltage | 1.2 Volts |
| RAM Size | 256 GB |
| Model Name | A-Tech Enterprise Series |
| Form Factor | RDIMM |
| Memory Speed | 2666 MHz |
| Model Number | AT128G2D4D2666RO43DSN12V |
| Item Type Name | computer-internal-memory |
| Number of Pins | 288 |
| Mfr Part Number | AT128G2D4D2666RO43DSN12V |
| Memory Generation | DDR4 |
| Compatible Devices | Server, Workstation |
| Data Transfer Rate | 21300 Megabytes Per Second |
| Memory Form Factor | RDIMM |
Ready to buy?
A-Tech 256GB Kit (2x128GB) DDR4 2666MHz PC4-21300 ECC RDIMM 8Rx4 (3DS 2S4Rx4) Octal Rank 1.2V ECC Registered DIMM 288-Pin Server & Workstation RAM Memory Upgrade Modules (A-Tech Enterprise Series) is available on Amazon with Prime shipping and the full Amazon returns policy. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-07-22. Price and availability subject to change.
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