sTR5 is AMD's socket for Ryzen Threadripper and Threadripper PRO workstation processors. It launched in 2023 with the Threadripper 7000 series and pairs with two chipsets, TRX50 and WRX90. It is a platform for work that uses dozens of cores, many PCIe devices or very large amounts of memory, not for gaming or general desktop use. The few boards sold in the UK are on the sTR5 motherboard deals page.
Cheapest sTR5 boards right now
What sTR5 is
sTR5 is a land grid array socket with 4,844 contacts, several times the size of a mainstream desktop socket. The pins are in the socket and the processor, which is far larger than a mainstream desktop chip, has flat pads. It is not compatible with the older Threadripper sockets (TR4, sTRX4 and sWRX8), and nothing from AM5 fits it.
Fitting the processor is a different job from a normal desktop build. The chip slides into a carrier frame on the socket, and the retention plate is tightened in a numbered order with a torque driver that AMD supplies with the processor. With this many pins, a damaged socket is an expensive fault, so an open-box board needs a very careful inspection before anything is fitted, and should arrive with its socket cover in place.
| TRX50 | WRX90 | |
|---|---|---|
| Processors | Threadripper and Threadripper PRO | Threadripper PRO |
| Memory channels | Four | Eight |
| Memory type | DDR5 registered (RDIMM) | DDR5 registered (RDIMM) |
| PCIe 5.0 lanes | Fewer | The most the platform offers |
| Aimed at | High-end desktop and studio workstations | Professional workstations |
Compatible processors
The socket takes the Threadripper 7000 series and the Threadripper 9000 series that followed it in 2025, in both standard and PRO versions. The 7000 series runs to 64 cores in the standard range and 96 cores in the PRO range. A board made before the 9000 series launched will need a BIOS update to run one, so check the maker's CPU support list; BIOS updates and CPU compatibility explains what to look for.
The pairing rule is that TRX50 takes both kinds of chip and WRX90 takes PRO chips only. A PRO processor in a TRX50 board works, but is limited to that board's four memory channels and its smaller number of PCIe lanes, so you pay for capability you cannot use. If you need eight memory channels or the full set of PCIe 5.0 lanes, you need WRX90 and a PRO chip together.
Threadripper processors have no integrated graphics. Some workstation boards carry a basic management controller with its own video output for remote administration, but plan on fitting a graphics card.
Memory
This is where buyers coming from a desktop platform get caught. sTR5 boards need registered DDR5, sold as RDIMM. Ordinary unbuffered desktop DDR5, the kind every AM5 and Intel board uses, will not work. Registered memory costs more per gigabyte and the choice at UK retail is narrower.
To get the memory bandwidth you are paying for, fill every channel: four matched modules on TRX50, eight on WRX90. The number of slots varies by board, so check the listing, and buy modules from the board's supported memory list where you can, because compatibility is less forgiving than on a desktop board.
Cooler compatibility
sTR5 keeps the cooler mounting of the earlier Threadripper sockets, so a cooler made for TR4, sTRX4 or sWRX8 fits. Coolers made for AM5, AM4 or Intel sockets do not, and would not cover the processor's heat spreader if they did. These chips are rated at 350 W, so choose a cooler built for Threadripper with a cold plate that covers the whole heat spreader, and make sure your case has room for it.
Case and power supply
Most sTR5 boards are larger than standard ATX. Makers describe them as E-ATX, or use the workstation sizes SSI-CEB and SSI-EEB, and the exact dimensions differ from board to board. Compare the figures in the specification with your case's stated motherboard support; the E-ATX form factor guide explains why the label alone is not enough. Expect more than one 8-pin CPU power connector, and on some boards extra PCIe power connectors for the slots, so check your power supply has the cables.
Platform lifespan and upgrade path
sTR5 has already had one new processor generation since launch, which is a reasonable sign for a workstation platform. AMD has not published an end date or a roadmap commitment for the socket in the way it has for AM5, so do not buy on the assumption that further generations will follow. Buy the core count you need now.
Who should buy into sTR5 in 2026
Buy it if your work is limited by core count, memory capacity, memory bandwidth or the number of PCIe devices: rendering, simulation, large code builds, several graphics cards or many NVMe drives. If your work is not limited by one of those, a Ryzen 9 on AM5 will do the job for a fraction of the platform cost, and for gaming it is often the faster choice. How to choose a motherboard covers mainstream builds.
Open-box boards do appear, and because these boards are expensive the saving can be substantial. The risk is higher to match: more pins to damage, and more accessories to go missing. Read Are Amazon Warehouse motherboards worth it? before ordering.
What to look for
- TRX50 or WRX90, chosen by the processor and the memory channels you need.
- Slot layout: how many full-length PCIe slots, at what speed, and how they are spaced for thick cards.
- Networking and storage: 10 Gb Ethernet, M.2 slot count and other storage connectors all vary by board.
- Dimensions against your case, and the power connectors against your power supply.
Current stock and prices are on the sTR5 motherboard deals page. For the other platforms, start from the list of sockets.
Questions people ask
Can I use normal desktop DDR5 in a Threadripper sTR5 board?
No. TRX50 and WRX90 boards need registered DDR5 (RDIMM). Unbuffered desktop DDR5 will not work, so budget for new memory if you are moving from a desktop platform.
What is the difference between TRX50 and WRX90?
TRX50 runs four memory channels and takes both Threadripper and Threadripper PRO processors. WRX90 runs eight memory channels, exposes more PCIe 5.0 lanes and takes Threadripper PRO processors only.
Will an older Threadripper processor fit sTR5?
No. Threadripper 1000, 2000, 3000 and the PRO 3000 and 5000 WX series use the older TR4, sTRX4 and sWRX8 sockets, and are not compatible with sTR5 boards. Coolers from those sockets do carry over.
Do sTR5 boards fit a normal ATX case?
Often not. Most are wider than standard ATX and are sold as E-ATX, SSI-CEB or SSI-EEB. Check the dimensions of the board against the motherboard sizes your case lists, and see our E-ATX boards page for other large boards.