Which servers use DDR5 RDIMM?
DDR5 registered memory (RDIMM) arrived with Intel’s 4th generation Xeon Scalable and AMD’s EPYC 9004 in late 2022 and early 2023, and every mainstream server since uses it. If your server is on the list below, its memory is DDR5 RDIMM — and it is the most valuable memory we buy, up to $3,390 a module today.
The platforms that take DDR5 RDIMM
| Processor | Memory speed | Servers |
|---|---|---|
| Intel Xeon Scalable 4th and 5th gen (Sapphire Rapids, Emerald Rapids) 2023–2024 | DDR5-4800 (4th gen), DDR5-5600 (5th gen) | Dell PowerEdge R660, R760, R860; HPE ProLiant DL360 and DL380 Gen11; Lenovo ThinkSystem SR630 V3, SR650 V3; Supermicro X13 |
| Intel Xeon 6 (Granite Rapids, Sierra Forest) 2024 on | DDR5-6400; MRDIMM-8800 on the 6900P series | Dell PowerEdge R670, R770; HPE ProLiant DL360 and DL380 Gen12; Lenovo ThinkSystem SR630 V4, SR650 V4; Supermicro X14 |
| AMD EPYC 9004 and 8004 (Genoa, Bergamo, Siena) 2022–2024 | DDR5-4800 | Dell PowerEdge R6615, R6625, R7615, R7625; HPE ProLiant DL325 and DL385 Gen11; Lenovo ThinkSystem SR645 V3, SR665 V3; Supermicro H13 |
| AMD EPYC 9005 (Turin) 2024 on | DDR5-6000 | Dell PowerEdge R6725, R7725; HPE ProLiant DL325 and DL385 Gen11; Lenovo ThinkSystem SR635 V3, SR655 V3; Supermicro H14 |
Speeds are the processor makers’ rated speeds at one module per channel; a module can be rated faster than the server runs it.
Everything older — Xeon E5 v3/v4, Xeon Scalable 1st to 3rd generation, EPYC 7001 to 7003, Dell PowerEdge 13th to 15th generation and HPE Gen9 to Gen10 Plus — takes DDR4 instead: sell DDR4 server RAM.
Workstations that take it too
Two workstation platforms use the same registered DDR5 as servers: Intel Xeon W-2400 and W-3400 (the W790 chipset), and AMD Threadripper 7000 and 9000 on TRX50 and WRX90 boards. Memory pulled from those machines sells as server RAM.
DDR5 that is not an RDIMM
Some small servers use unbuffered ECC DDR5 (ECC UDIMM) instead: Intel Xeon E-2400 and AMD EPYC 4004 machines, for example. It is still ECC server memory and we buy it, but an ECC UDIMM will not work in a server that wants RDIMMs, and the other way round. Ordinary desktop DDR5 — no ECC, no register — is priced as desktop memory.
How to tell a DDR5 RDIMM
- The label.
PC5-4800B-RB0— PC5 is DDR5, and the R after the dash means registered. A desktop module reads U there. - The part number. Samsung RDIMMs start
M321R, SK hynixHMCwith anRnear the end of the core code, MicronMTCwithRCbefore the speed. How to read them. - The chips. An RDIMM has a register chip in the middle of the module and usually a ninth or tenth memory chip per side for ECC.
- The notch. DDR5 RDIMMs and desktop DDR5 are keyed differently, so one cannot be pushed into the other’s slot.
What DDR5 RDIMMs pay today
New offers per module — $889 for a 64GB module when the speed is not known. Used offers are on each size’s page.
| Capacity | Speed not known | 4800 | 5600 | 6400 | 7200 | 8000 | 8400 | 8800 |
|---|---|---|---|---|---|---|---|---|
| 8GB DDR5 | $56 | $57 | $57 | $57 | — | — | — | — |
| 16GB DDR5 | $225 | $223 | $245 | $249 | — | — | — | — |
| 24GB DDR5 | $309 | $306 | $311 | $309 | — | — | — | — |
| 32GB DDR5 | $456 | $460 | $482 | $482 | — | $486 | $482 | $478 |
| 48GB DDR5 | $673 | $673 | $667 | $678 | — | $678 | $673 | $678 |
| 64GB DDR5 | $889 | $885 | $1,110 | $1,110 | $1,098 | $1,120 | $1,130 | $1,130 |
| 96GB DDR5 | $1,345 | $1,444 | $1,457 | $1,681 | — | $1,666 | $1,695 | $1,681 |
| 128GB DDR5 | $1,808 | $1,905 | $2,147 | $2,240 | — | $2,240 | $2,220 | $2,260 |
| 256GB DDR5 | $3,361 | $3,361 | $3,390 | $3,361 | — | $3,390 | $3,361 | $3,331 |