How to read Samsung, SK hynix and Micron server RAM labels
A server memory sticker tells you everything that sets the module’s value — generation, size, speed and type — once you know where to look. Here is how to read the standard label line, and the part numbers of the three companies that make almost all server DRAM.
Two codes on every sticker
Most labels carry two things: a JEDEC line that reads the same whatever the brand (32GB 2Rx4 PC4-3200AA-RB2), and the maker’s part number (M393A4K40DB3-CWE). Either one is enough to price the module; the part number is the more exact.
The PC4 / PC5 line
Take PC4-2933Y-RB2. PC4 is DDR4; PC5 is DDR5 and PC3 is DDR3. 2933 is the speed in MT/s. Older DDR4 and DDR3 labels print the bandwidth instead of the speed, so PC4-19200 is DDR4-2400 and PC4-25600 is DDR4-3200. The letter after the speed is the timing grade.
After the dash, the first letter is the module type: R for a registered DIMM (RDIMM), L for load-reduced (LRDIMM) and E for unbuffered ECC. The rest identifies the board design and does not matter to the price. A DDR5 example: PC5-4800B-RB0 is a DDR5-4800 RDIMM.
The rank line: 2Rx4, 1Rx8
Before the PC code comes the size and organisation — 32GB 2Rx4 is 32GB in two ranks built from 4-bit-wide chips. Ranks (1R, 2R, 4R, 8R) and chip width (x4, x8) matter to the server’s memory population rules; they do not change what a module is worth to us.
Samsung part numbers
Samsung server memory starts M393 (DDR4 RDIMM), M386 (DDR4 LRDIMM) or M321R (DDR5 RDIMM). The two characters after the generation letter give the size, and the three letters after the dash give the speed.
M393A · M386A— DDR4 RDIMM · DDR4 LRDIMM (M391A is DDR4 ECC UDIMM)2K · 4K · 8G · AG— DDR4 16GB · 32GB · 64GB · 128GB (K and G mean the same size)-CRC · -CTD · -CVF · -CWE— DDR4-2400 · 2666 · 2933 · 3200 (-CAE is also 3200)M321R + 2G · 4G · 8G— DDR5 RDIMM, 16GB · 32GB · 64GB-CQK— DDR5-4800
Worked example: M393A4K40DB3-CWE
M393— DDR4 RDIMM4K— 32GB40— built from x4 chipsB— standard package-CWE— DDR4-3200
Sell M393A4K40DB3-CWE — today’s offer and full specifications.
Worked example: M321R8GA0BB0-CQK
M321R— DDR5 RDIMM8G— 64GBA0— built from x4 chips-CQK— DDR5-4800
Sell M321R8GA0BB0-CQK — today’s offer and full specifications.
SK hynix part numbers
SK hynix DDR4 server modules start HMA and DDR5 modules start HMC. On a DDR4 part the character just before the G gives the size and the letter after it the type; the two letters after the dash are the speed.
HMA82G · HMA84G · HMAA8G · HMABAG— DDR4 16GB · 32GB · 64GB · 128GB…GR7 · …GL7— RDIMM · LRDIMM-UH · -VK · -WM · -XN— DDR4-2400 · 2666 · 2933 · 3200HMCG7 · HMCG8 · HMCG9 · HMCT0— DDR5 16GB · 32GB · 64GB · 128GB…EBR— DDR5-4800 RDIMM
Worked example: HMA84GR7CJR4N-XN
HMA— SK hynix DDR4 module4G— 32GBR— RDIMMR4— built from x4 chips-XN— DDR4-3200
Sell HMA84GR7CJR4N-XN — today’s offer and full specifications.
Micron part numbers
Micron DDR4 server modules start MTA and DDR5 modules start MTC. On DDR4 the number before G72 is the size in 8GB steps and the letter after it is the type; on DDR5 the speed sits after RC.
2G72 · 4G72 · 8G72— DDR4 16GB · 32GB · 64GBPZ · LZ— RDIMM · LRDIMM-2G3 · -2G6 · -2G9 · -3G2— DDR4-2400 · 2666 · 2933 · 3200…4 or 8, then 5 · X · 6 · W, then S— DDR5 32GB · 48GB · 64GB · 96GBRC48B · RC56B · RC64B— DDR5-4800 · 5600 · 6400 RDIMM
Worked example: MTA36ASF4G72PZ-3G2
MTA— Micron DDR4 module4G72— 32GB, with ECC (72 bits wide)P— RDIMM-3G2— DDR4-3200
Sell MTA36ASF4G72PZ-3G2 — today’s offer and full specifications.
Worked example: MTC40F2046S1RC48BA1
MTC— Micron DDR5 module46— built from x4 chips, 64GBRC— RDIMM48B— DDR5-4800
Sell MTC40F2046S1RC48BA1 — today’s offer and full specifications.
HPE, Dell and Lenovo labels
Memory that shipped in a ProLiant, PowerEdge or ThinkSystem usually has a second sticker with the server maker’s own number. HPE prints an option number ending -B21 and a spare number ending -001; Dell prints its own part number; Lenovo prints a FRU and an option part number. The memory maker’s sticker is normally still on the module too, and either code prices it — the module inside is the same Samsung, SK hynix or Micron part, and gets the same offer.
Try yours
Type the part number from your sticker and we read it for you:
What it is worth, size by size: how much is used server RAM worth? Every part number we buy is listed on the DDR5 and DDR4 server RAM pages.