AMD's WRX90 is the workstation platform for Threadripper PRO processors on socket sTR5: up to 96 cores, eight channels of DDR5 ECC registered memory and up to 2TB of RAM. This guide explains what WRX90 is, which motherboards and workstations use it, and how to choose memory for each: the module type, the speed for your processor and the kit size that fills all eight channels.
The short answer: every WRX90 system takes DDR5 ECC RDIMM, one module per channel in eight slots. Install eight identical modules for full bandwidth. Threadripper PRO 9000 WX runs DDR5-6400; Threadripper PRO 7000 WX runs DDR5-5200, so faster modules work and run at 5200.
What WRX90 is
WRX90 launched in late 2023 with the Threadripper PRO 7000 WX series and became the home of the Threadripper PRO 9000 WX series in 2025. It shares the sTR5 socket with TRX50, the platform for the non-PRO Threadripper, but the two are not the same. WRX90 doubles the memory channels and capacity and opens all of the processor's PCIe 5.0 lanes:
| WRX90 | TRX50 | |
|---|---|---|
| Processors | Threadripper PRO 7000 WX and 9000 WX only | Threadripper 7000 and 9000 X-series (PRO also supported) |
| Memory channels | 8 | 4 |
| Maximum memory | 2TB | 1TB |
| Memory type | DDR5 ECC RDIMM | DDR5 ECC RDIMM |
| PCIe 5.0 lanes from the CPU | 128 | 48 (80 with 9000-series processors) |
For the TRX50 boards, see Threadripper motherboard memory, which also covers the older WRX80, TRX40 and X399 platforms.
Threadripper PRO 7000 WX and 9000 WX: what changes for memory
- Threadripper PRO 7000 WX (2023, up to the 96-core 7995WX): DDR5-5200 RDIMM, eight channels.
- Threadripper PRO 9000 WX (2025, up to the 96-core 9995WX): DDR5-6400 RDIMM, eight channels. The 9000 WX series drops into existing WRX90 boards after a BIOS update.
The memory type does not change between the two: the same DDR5 ECC RDIMMs work with both, and a faster module runs at the speed the processor supports. What changes is the speed you can use. A system that starts on a 7000 WX processor and moves to a 9000 WX later gains the most from DDR5-6400 modules bought now.
WRX90 motherboards
| Board | Memory | Platform notes | NEMIX RAM listings |
|---|---|---|---|
| ASUS Pro WS WRX90E-SAGE SE | 8 DDR5 ECC RDIMM slots, up to 2TB (1DPC) | EEB, seven PCIe 5.0 x16 slots, dual 10G LAN, BMC | DDR5-4800 · DDR5-5600 · DDR5-6400 |
| ASRock WRX90 WS EVO | 8 DDR5 ECC RDIMM slots, up to 2TB | EEB, seven PCIe 5.0 x16 slots, dual 10G LAN, BMC | DDR5-4800 · DDR5-5600 · DDR5-6400 |
| GIGABYTE MH53-G40 | 8 DDR5 RDIMM slots, DDR5-6400 with 9000 WX, DDR5-5200 with 7000 WX | E-ATX, six PCIe 5.0 x16 slots | DDR5-6400 |
All three boards are single-socket, with one DIMM per channel. Each listing offers module sizes from 16GB or 32GB up to 128GB, as single modules and matched kits of up to eight.
WRX90 workstations
Most WRX90 systems are bought as complete workstations. The memory rules are the same; the listing for your model shows the sizes and kits that fit it.
- Dell Precision 7875 Tower (Threadripper PRO 7000 WX): DDR5-4800 listing and DDR5-5600 listing, with kits up to 1TB.
- Lenovo ThinkStation P8: a Threadripper PRO 7000 WX listing at DDR5-4800 and a Threadripper PRO 9000 WX listing at DDR5-6400. Check which processor your P8 has before ordering.
- GIGABYTE W773-H5D (on the MH53-G40 board, also sold by Thinkmate): DDR5-6400 listing, eight slots, kits up to 1TB.
- CIARA KRONOS 546-G2: DDR5-6400 listing, eight slots, kits up to 1TB.
For other Dell and Lenovo workstations, see Dell Precision workstation memory and Lenovo ThinkStation memory.
How to choose WRX90 memory
1. Module type: DDR5 ECC RDIMM only
WRX90 takes registered ECC memory. Desktop UDIMMs and ECC UDIMMs have a different design and will not work, and non-ECC memory is not supported. Every module in the system should be the same part: same capacity, speed and rank.
2. Speed: match the processor
Buy DDR5-6400 for a Threadripper PRO 9000 WX system. A 7000 WX processor runs memory at up to DDR5-5200: DDR5-5600 and DDR5-6400 modules run at 5200 there and keep the option of a 9000 WX upgrade open, while DDR5-4800 modules run at 4800 and cost the least. All are JEDEC-standard and run at the speed the processor supports.
3. Fill all eight channels
Each of the eight slots is its own memory channel. Eight identical modules give the full bandwidth that rendering, simulation, compilation and AI workloads depend on. Four modules run, but at about half the bandwidth; two modules leave three-quarters of it unused.
4. Pick the capacity
| Kit | Total | Typical use |
|---|---|---|
| 8 × 16GB | 128GB | CAD, video editing, development |
| 8 × 32GB | 256GB | 3D rendering, large codebases, virtual machines |
| 8 × 64GB | 512GB | Simulation, scientific computing, multi-GPU AI work |
| 8 × 128GB | 1TB | Very large datasets, in-memory analytics, model training |
Choose the module size that reaches your target with all eight slots filled, rather than leaving slots empty for later: mixing module sizes later can lower the speed or unbalance the channels. Browse every DDR5 RDIMM module if you are matching an existing part.
Buying for a studio, lab or engineering team
WRX90 workstations are usually bought in groups: a render farm, a simulation lab, a university research group or a team of engineers on the same build. Send us the board or workstation model and the number of systems, and we will quote matched eight-module kits for every machine as one order. Purchase orders, net terms and volume pricing are available for business, government and education buyers: request a quote or contact us.
Frequently asked questions
What memory does a WRX90 motherboard take?
DDR5 ECC Registered memory (RDIMM), one module per channel in eight slots. Unbuffered desktop DIMMs, including ECC UDIMMs, will not work, and non-ECC memory is not supported.
What is the difference between WRX90 and TRX50?
Both use the sTR5 socket. WRX90 is the Threadripper PRO platform with eight memory channels, up to 2TB and 128 PCIe 5.0 lanes from the processor. TRX50 has four memory channels and up to 1TB. WRX90 boards accept only Threadripper PRO WX processors; the non-PRO Threadripper 7000 and 9000 X-series run on TRX50.
Which memory speed should I buy for Threadripper PRO 9000 WX?
Threadripper PRO 9000 WX processors run DDR5-6400 RDIMMs, so DDR5-6400 modules reach the full rated speed. Threadripper PRO 7000 WX processors run DDR5-5200, so DDR5-5600 or DDR5-6400 modules work there and run at 5200.
Can I use four modules instead of eight?
Yes, the system will run, but it uses only four of the eight memory channels and loses about half of the memory bandwidth. For rendering, simulation and AI workloads, eight identical modules are the right configuration.
How much memory can a WRX90 system hold?
The platform supports up to 2TB (eight 256GB RDIMMs). Our WRX90 listings offer matched kits up to 1TB with eight 128GB modules; contact us for larger configurations.
Do I need a BIOS update for a Threadripper PRO 9000 WX processor?
Boards that launched with the 7000 WX series need a BIOS update before a 9000 WX processor will run. ASUS, ASRock and GIGABYTE all publish 9000 WX support BIOS releases. Update the BIOS with the old processor installed, then fit the new one and its memory.
Why NEMIX RAM for WRX90
Every WRX90 listing names the exact board or workstation it fits and offers only the module sizes and kits that suit its eight channels. Researched, matched, and compatibility-tested by NEMIX RAM, a US-based server memory specialist since 1993, and backed by a lifetime warranty. Questions about a specific system? Send us the board or workstation model and we will confirm the right module before you order.