Samsung New DDR5 RDIMM Part Number Decoder

Samsung DDR5 memory part numbers are changing. In 2026, Samsung introduced a new DDR5 RDIMM part number format that uses codes like MDRR644QDBC2-3L000 and MDRRWM4QKBC2-4D000.

These new part numbers will gradually replace the older Samsung DDR5 naming style used on modules such as M321RAJA0MB2-CCP, M321RYGA0PB0-CWM and M321R8GA0EB2-CCP.

At first, the new format looks difficult to read. But each part of the code has a meaning: module type, capacity, die organization, die generation, speed, package, revision, RCD/PMIC combination and handling code.

A Samsung DDR5 RDIMM part number such as MDRR644QDBC2-3L000 can be broken down into sections.

MDRR identifies the module family. In this format, it refers to a Samsung DDR5 memory module, with R indicating an RDIMM module.

The capacity code tells you the module density:

The die organization code shows whether the DRAM is x4, x8 or x16.

The die generation code identifies the Samsung DRAM generation. In the examples below, Q refers to Samsung 17th generation Q-die.

The speed code is one of the most important parts:

The 64 code means 64 GB capacity using 16 Gb DRAM. The 4 means x4 die organization. Q indicates Samsung Q-die, and D means DDR5-6400. C2 identifies the product revision. 3L0 identifies the RCD and PMIC combination.

MDRR644QDBC2-3L000 = Samsung 64 GB DDR5-6400 RDIMM, x4, Q-die, standard handling.

The WM code means 96 GB capacity using 24 Gb DRAM. The 4 means x4 organization. Q identifies Samsung Q-die, and K indicates DDR5-7200.

The difference between 4D0 and 4G0 is the RCD/PMIC vendor combination. For most buyers, this matters only when strict BOM matching is required.

MDRRWM4QKBC2-4D000 = Samsung 96 GB DDR5-7200 RDIMM, x4, Q-die, RNS Gen4 RCD + RNS PMIC. MDRRWM4QKBC2-4G000 = Samsung 96 GB DDR5-7200 RDIMM, x4, Q-die, MTG Gen4 RCD + MPS PMIC.

The older Samsung DDR5 part numbers such as M321RAJA0MB2-CCP were widely used across server memory product listings and OEM qualification references.

The new MDRR-style format encodes more detail directly in the part number. It makes newer DDR5 modules easier to decode once you know the structure, especially for 24 Gb-based capacities such as 96 GB RDIMMs.

For buyers, the main things to check are: capacity code (64 or WM), speed code (D for DDR5-6400 or K for DDR5-7200), module type (RDIMM), and RCD/PMIC code for strict part matching.

MDRR644QDBC2-3L000 Samsung 64 GB DDR5-6400 RDIMM

MDRRWM4QKBC2-4D000 Samsung 96 GB DDR5-7200 RDIMM

MDRRWM4QKBC2-4G000 Samsung 96 GB DDR5-7200 RDIMM

Need help matching a Samsung DDR5 RDIMM to a server or OEM part number? Contact CoreWave Labs and we can verify the correct module before ordering.