Samsung DDR4 Part Number Guide

The quick answer: identify the product level before decoding

A code can be perfectly valid and still answer the wrong question. The component number describes one packaged DRAM device. The module number describes the assembled DIMM or SODIMM. A PC4 line summarizes characteristics in a standardized label format, while SPD reports electronic configuration data to the host. Serial, date and lot markings add traceability but are not orderable part numbers.

Key takeaways

• K4A… identifies a Samsung DDR4 SDRAM component; M… identifies an assembled memory module.
• Component density is stated in gigabits; module capacity is sold in gigabytes. An 8Gb chip is not an 8GB DIMM.
• The hyphenated suffix is part of the orderable component identity and can distinguish package, temperature/power option and speed bin in the relevant ordering table.
• M378…, M471…, M393… and M386… are useful routing clues, not full compatibility decisions.
• Matching capacity and DDR4-3200 does not prove interchangeability. Module type, rank, device width, ECC/buffering, SPD and platform rules still control.
• A plausible label or part number does not prove current production, authenticity or storage condition.

Technical basis: Samsung's DDR4 overview, exact product records and family data sheets. Technical review date: 28 August 2026.

Component MPN, module MPN, PC4 label and SPD are related—not interchangeable

This separation prevents a common arithmetic failure: reading the density and width of one DRAM package as the capacity and rank structure of a complete module.

Worked component example: K4A4G085WE-BCRC

Samsung's official 4Gb E-die DDR4 data sheet lists K4A4G085WE-BCRC as a 4Gb device organized as 512M × 8 in a 78-ball FBGA package. In that exact ordering table, the suffix identifies the commercial-temperature, normal-power DDR4-2400 option with a 17-17-17 speed bin.

This segmentation is tied to Samsung's 4Gb E-die ordering table. It is evidence for this family, not a promise that every Samsung suffix ending in RC is otherwise equivalent.

A purchasing system should store the full MPN as text. It must not drop the hyphen, truncate the final characters or reconstruct the MPN from descriptive fields.

Density and organization require separate checks

The 4Gb rating means four gigabits, not four gigabytes. For the documented 512M × 8 organization, 512M locations × 8 bits = 4096 Mbits = 4 Gbits, or 0.5 GB of primary capacity per component. Eight x8 devices provide a 64-bit non-ECC data path for one rank, so eight 4Gb components provide 4GB. Additional ranks or ECC check bits require more devices.

Samsung's family tables also distinguish x4, x8 and x16 organizations. The same density does not guarantee the same package, addressing, bank structure, page size, timing detail or PCB routing. Match the complete base number and suffix—not just K4A4G….

Source: Samsung 4Gb E-die DDR4 SDRAM Data Sheet, Rev. 1.6.

Use this six-step decoding and approval method

1. Capture the string exactly.Record capitalization, hyphen and every suffix character. Keep full label photographs, SPD output and supplier paperwork.
2. Classify the identity level.Separate component MPN, module MPN, PC4 description, SPD part-number field, distributor SKU and serial/date/lot markings.
3. Open the exact Samsung record.Use the product page, density/die-specific component data sheet, module data sheet or official SPD file. Do not decode from an unrelated generation.
4. Reconcile electrical and mechanical fields.Confirm density or capacity, x4/x8/x16, rank, ECC/buffering, data rate, voltage, package or pin count and temperature grade.
5. Check platform and lifecycle evidence.Review system QVL/manual, CPU memory-controller limits, BIOS, population rules, current Samsung status and any applicable PCN/PDN history.
6. Freeze the approved identity.Quote the complete MPN, prohibit silent substitutions and store the document revisions and traceability requirements used for approval.

How to route Samsung M-series DDR4 module numbers

Samsung does not publish one simple public rule that safely decodes every character in every DDR4 module MPN. Use the visible prefix to locate the likely family, then let the exact product record or module data sheet prove the type, capacity, rank, speed and composition.

Form factor is a compatibility field, not a visual preference

A DDR4 SODIMM is physically shorter than a full-size DIMM and uses a different connector format. Even within the correct form factor, capacity, rank, device width, ECC/buffering, timings and platform rules still matter.

A seller's “Samsung DDR4 laptop RAM” title is therefore insufficient. Ask for the complete M471 MPN, label photo, speed/rank description and SPD evidence when qualification risk justifies it.

Three documented cases show what the full record adds

These are documentation walkthroughs. They do not claim YURUNOX supplied, tested or qualified the listed parts, and they do not establish that another part with a similar prefix is equivalent.

Rank, ECC, density and speed: the calculations buyers should cross-check

ECC capacity is not counted twice

A typical x8 ECC rank uses nine x8 devices: eight for the 64-bit primary data path and one for eight check bits. The extra device protects data; it does not add separately addressable user capacity. A rank is also a logical 64-bit or 72-bit set, not simply “one side” of a module.

CAS latency needs time, not only a CL number

An approximate CAS time is CL divided by the real clock frequency. DDR4-2400 CL17 uses a 1200MHz clock and is about 14.17ns; DDR4-3200 CL22 uses a 1600MHz clock and is about 13.75ns. Real memory latency also includes other timings, controller behavior, refresh, rank activity and workload. Never approve a substitute from CL alone.

Identifier triage tool: collect the right evidence

This tool does not guess a hidden decoder result. It routes the identifier to the minimum evidence set needed for a quote, substitution review or incoming decision.

Turn the decoded identity into an RFQ and receiving control

YURUNOX is an independent electronic-component sourcing partner, not the manufacturer of Samsung memory. A practical Samsung sourcing request should connect the approved manufacturer identity to supplier evidence, platform requirements and receiving criteria.

RFQ and incoming-inspection checklist

• Exact identity.Samsung manufacturer name and complete MPN, including the hyphen and every suffix character.
• Product level.State whether the request is for a DRAM component or assembled UDIMM, ECC UDIMM, RDIMM, LRDIMM or SODIMM.
• Capacity and organization.Record Gb per component or GB per module, x4/x8/x16, rank count, ECC and component composition.
• Speed and voltage.Specify data rate, official speed bin/timings, 1.2V requirement and allowed downclock behavior.
• Mechanics.Confirm FBGA package/ball count for components or pin count, outline, height and keying for modules.
• Platform approval.Provide system model, CPU, QVL/manual, BIOS level, DIMMs per channel and population rules.
• Lifecycle and change control.Request current Samsung status, applicable PCN/PDN history and written approval for any alternate.
• Traceability.Define accepted source, invoice chain, packing, date/lot restrictions, quantity split and warranty.
• Receiving evidence.Require label and package photos, character-by-character MPN comparison and SPD reconciliation for modules.
• Exception handling.Quarantine unexplained label, SPD, component, date/lot or packaging differences under the buyer's quality-assurance process.

The platform is part of the specification

CPU memory controllers can reduce supported speed as ranks or DIMMs per channel increase. System vendors may restrict x4/x8 topology, capacity per slot, mixed ranks, ECC, RDIMM/LRDIMM combinations or population order.

A memory module can be genuine and electrically functional yet still be unsupported in the target server or PC. Keep platform approval separate from product identity and supplier authenticity checks.