How to Read a RAM Label: Samsung, Hynix, Micron Part Numbers Decoded
By the SellUsedRAM bench · Reviewed August 12, 2026 · About SellUsedRAM
A RAM label tells you everything a buyer needs to price the module — capacity, generation, speed, rank, and type — once you know each manufacturer's pattern. This guide is the decoder ring for the three DRAM makers whose names are actually on the chips (Samsung, SK Hynix, Micron) plus the two third-party formats you will meet most often (Kingston, Crucial). No software required; if the machine still runs, though, the OS can read all of this for you — see how to tell what RAM you have.
Start with the generic line
Most labels carry a JEDEC-style summary such as 16GB 2Rx8 PC4-3200AA-RE1. Read it in four pieces: capacity (16GB), rank and chip width (2Rx8 — two ranks of x8 chips; the full story is in what rank markings mean), the speed code (PC4 = DDR4; PC4-25600 style numbers are bandwidth, PC4-3200AA style are the data rate), and a final letter block whose first letter is the module type — R registered, U unbuffered, E ECC unbuffered, L load-reduced, S SODIMM. Speed translations worth memorizing: DDR4-2133 = PC4-17000, 2400 = PC4-19200, 2666 = PC4-21300, 2933 = PC4-23400, 3200 = PC4-25600; DDR5-4800 = PC5-38400, 5600 = PC5-44800, 6000 = PC5-48000.
Samsung: M393A4K40CB2-CVF
The prefix names the family: M393 = DDR4 RDIMM, M386 = DDR4 LRDIMM, M391 = DDR4 ECC UDIMM, M378 = DDR4 UDIMM, M471 = DDR4 SODIMM; for DDR5, M321 = RDIMM, M323 = UDIMM, M425 = SODIMM. The middle block encodes capacity and organization (A4K40 is 32GB dual-rank x4; A8G40 is 64GB). The suffix pair after the dash is speed: CPB 2133, CRC 2400, CTD 2666, CVF 2933, CWE 3200. So M393A4K40CB2-CVF reads: 32GB DDR4-2933 registered — the module on our 32GB DDR4-2933 RDIMM page (currently $93–$108 per module).
SK Hynix: HMA84GR7CJR4N-WM
HMA is DDR4 (HMT was DDR3, HMC is DDR5). The digits after it encode capacity — 84G = 32GB, 8G = 8GB, AA8G = 64GB — and the letter block tells the type: R for registered (GR7 here), U for unbuffered, S for SODIMM. R4 near the end is the chip width (x4). The tail letters are speed: TF 2133, UH 2400, VK 2666, WM 2933, XN 3200. HMA84GR7CJR4N-WM is therefore another 32GB DDR4-2933 RDIMM — same market row as the Samsung above.
Micron: MTA36ASF4G72PZ-2G9E1
Micron leads with the chip count: MTA36 = 36 DRAM packages (a dual-rank x4 ECC module), MTA18 = 18, MTA9 = 9. The block ASF4G72 encodes a 4G-deep, 72-bit organization — 32GB with ECC; ASF8G72 doubles it to 64GB, like the 64GB DDR4-3200 RDIMM (currently $288–$352 per module). PZ marks a registered module. The tail is speed: 2G3 2400, 2G6 2666, 2G9 2933, 3G2 3200. DDR5 Microns start with MTC.
Kingston and Crucial
Kingston's server line reads almost like English: KSM29RD4/64HAR is Server Premier (KSM), 2933 (29), registered dual-rank x4 (RD4), 64GB (/64) and currently pays $165–$192; the trailing letters encode the DRAM die source. Crucial puts capacity first: CT32G4DFD832A is Crucial (CT), 32GB (32G), DDR4 (4), with the speed in the tail digits (32 = 3200); an S in the form block makes it a SODIMM, as in CT32G4SFD832A. Consumer kits from G.Skill, Corsair, and friends follow their own schemes — for those, the sticker's plain-English line (capacity, DDR generation, speed) plus a photo is all a buyer needs.
When the sticker is missing, damaged, or wrong
Modules get relabeled, stickers fall off, and counterfeits exist. The ground truth lives in the SPD chip on the module, which is what our bench reads on every stick at intake — the SPD always wins over the sticker. If you cannot identify a module, do not guess: paste whatever is legible into the quote form, which fuzzy-matches part numbers with or without dashes, or check the label against the rows on the Payout Index.
FAQ
What does PC4-25600 mean on my RAM?
DDR4 with 25,600 MB/s of theoretical bandwidth — which is DDR4-3200. Divide the PC number by eight to get the data rate; PC5 numbers work the same way for DDR5.
What does the -CVF suffix mean on Samsung memory?
It is Samsung's speed code for DDR4-2933. The neighboring codes are CPB (2133), CRC (2400), CTD (2666), and CWE (3200) — one sticker letter-pair is often the entire difference between two price tiers.
My part number is not on your site. Is it worthless?
No — the catalog lists the most-traded configurations, not everything we buy. Paste the exact part number into the quote form; matching variants (different die revisions, vendor-branded labels) is our job, not yours.
Does the manufacturer on the label change the value?
Samsung, SK Hynix, and Micron modules of the same specification price the same tier and are equally liquid. Vendor stickers on top (Dell, HPE, Lenovo) do not change the underlying module or its value.
Label decoded? The quote form turns that part number into a firm figure within four business hours.