Samsung 128GB 2666MHz DDR4 PC4-21300 ECC Registered CL19 288-Pin DIMM 1.2V Octal Rank x4 Memory Module — M393AAK40B42-CWD6Q

The Samsung M393AAK40B42-CWD6Q is a 128GB DDR4-2666MHz ECC Registered (RDIMM) server memory module operating at 1.2V with CL19 latency. Featuring a 288-pin interface and Octal Rank x4 configuration, it delivers maximum-density enterprise memory for multi-processor server platforms. The CWD6Q suffix denotes a specific Samsung production revision of the M393AAK40B42 family.

Key Features

• 128GB ultra-high-capacity ECC Registered DIMM for enterprise servers
• DDR4-2666MHz (PC4-21300) for reliable enterprise memory performance
• Registered DIMM (RDIMM) for stability in dense multi-DIMM configurations
• Octal Rank x4 configuration for maximum per-slot memory density
• 1.2V low-voltage operation for energy-efficient server operation
• 288-pin interface — standard DDR4 RDIMM form factor

Product Specifications

• Part Number: M393AAK40B42-CWD6Q
• Manufacturer: Samsung
• Model: 128GB DDR4-2666 ECC Registered DIMM (CWD6Q revision)
• OEM Status: Genuine Samsung OEM
• Capacity: 128GB
• Type: DDR4 ECC Registered DIMM (RDIMM)
• Speed: 2666MHz (PC4-21300)
• CAS Latency: CL19
• Voltage: 1.2V
• Rank / Organization: Octal Rank x4
• Pins: 288-Pin
• ECC: Yes

Memory Specifications

• Capacity: 128GB
• DIMM Type: Registered ECC (RDIMM)
• DDR Generation: DDR4
• Pin Count: 288-Pin
• Rank: Octal Rank (8Rx4)
• Voltage: 1.2V
• ECC: Yes (Error-Correcting Code)
• Production Revision: CWD6Q

Performance Specifications

• Speed: DDR4-2666MHz
• Bandwidth: PC4-21300
• CAS Latency: CL19
• XMP / JEDEC: JEDEC standard

Use Cases

• Maximum-capacity enterprise server memory for dual and quad-socket platforms
• Large-scale virtualization hosts requiring massive memory pools
• In-memory database and analytics workloads
• HPC and AI/ML workloads requiring high-capacity ECC RDIMM

Compatibility

• Compatible with servers supporting DDR4 ECC Registered (RDIMM) memory
• Compatible with Intel Xeon Scalable and AMD EPYC server platforms
• Octal Rank — verify server maximum rank support per channel before ordering
• Verify server QVL (Qualified Vendor List) before ordering

Frequently Asked Questions

What does Octal Rank x4 mean?

Octal Rank x4 means the module has eight ranks of memory chips, each using x4-wide chips. This maximizes per-slot capacity but may limit DIMMs per channel — verify your server's rank support before ordering.

What is the difference between M393AAK40B42-CWD and M393AAK40B42-CWD6Q?

Both are 128GB DDR4-2666 ECC RDIMM modules from the same Samsung family. The CWD6Q suffix denotes a specific production revision — they are functionally equivalent.

Is this module compatible with Intel Xeon Scalable processors?

Yes, it is compatible with Intel Xeon Scalable server platforms supporting DDR4-2666 ECC RDIMM. Verify your specific server's QVL before ordering.

The Samsung M393AAK40B42-CWD6Q 128GB DDR4-2666 ECC Registered DIMM delivers maximum-capacity enterprise memory for the most demanding server workloads. Order today for genuine Samsung RDIMM quality at 128GB per slot.