A-Tech 128GB DDR4 2666 ECC RDIMM Server Memory
A 128GB DDR4 2666MHz ECC RDIMM module with CL19 latency and 1.2V operation for server workloads
- Total capacity128 GB
- Rated speedDDR4 2666 (PC4 21300)
- ChipsetSamsung Chipset
- CAS latencyCL19
- Rated voltage1.2 V
- Buffer typeRegistered
- 128 GB capacity handles heavy server workloads
- DDR4 2666 MHz speed delivers fast data throughput
- ECC registered design corrects errors for reliability
- 20 V operation matches standard DDR4 voltage
- 288-pin DIMM form factor fits compatible server slots
128GB DDR4 2666 ECC RDIMM Server Memory
This A-Tech module provides 128GB of registered ECC DDR4 memory in a single 288-pin DIMM. It is built for servers and workstations that require high-density, error-correcting memory to maintain data integrity under heavy workloads. The module uses Samsung chipset and operates at 2666MHz with CL19 latency.
DDR4 2666 registered DIMM constraints
Registered DIMMs add a buffer that reduces electrical load on the memory controller, allowing higher module counts per channel than unbuffered memory. This module requires a platform that supports DDR4 RDIMM with ECC and the 2S4Rx4 (8Rx4) 3DS/TSV rank structure. Systems limited to UDIMM or lower rank counts will not accept it.
128GB single-module capacity decides fit
The 128GB density in one slot is the specification that determines whether this part suits your build. Verify that your motherboard or server lists 128GB RDIMM support per slot and the 8Rx4 rank configuration before purchase. Buyers who need lower-density modules or unbuffered memory cannot use this kit.
How it compares
Measured against everything we stock in ECC Server RAM, at today’s prices. Recalculated every night.
- Price $531.99
- Pricier than about 71% of the 6,523 comparable items (median $188.99).
- Total capacity 128 GB
- Higher than about 90% of the 6,064 comparable items (median 32 GB).
- Price per GB $4.16 per GB
- Cheaper than about 80% of the 6,064 comparable items (median $7.25 per GB).
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Specifications
| Product | |
|---|---|
| Brand name | A-Tech |
| Product line | Compatible Replacement for Samsung |
| Model name | M393AAK40B42-CWD |
| Total capacity | 128 GB |
| Performance | |
| Rated speed | DDR4 2666 (PC4 21300) |
| Processor | |
| Chipset | Samsung Chipset |
| Memory | |
| CAS latency | CL19 |
| ECC support | Yes |
| Buffer type | Registered |
| Memory rank | 2S4Rx4 (8Rx4) |
| Power | |
| Rated voltage | 1.2 V |
Questions about this item
Is this 128 GB module the right choice if I need a single high-capacity DDR4 2666 ECC RDIMM?
Yes, this is a single 128 GB DDR4 2666 ECC registered DIMM using Samsung chipset, built as a compatible replacement for the Samsung M393AAK40B42-CWD module.
What does the PC4-21300 rating tell me about real-world throughput?
PC4-21300 indicates a peak transfer rate of 21 300 MB/s at 2666 MT/s; actual bandwidth depends on the platform’s memory controller and channel population.
How does the 288-pin DDR4 RDIMM interface limit what systems can use this module?
The 288-pin DDR4 registered DIMM form factor fits only DDR4 server or workstation boards that support ECC RDIMMs and 3DS/TSV 8Rx4 modules at 1.2 V.
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