AMD Ryzen Threadripper PRO 3995WX socket: sWRX8
The AMD Ryzen Threadripper PRO 3995WX uses sWRX8, the 4094-contact LGA socket for Threadripper PRO workstations. It is a 64-core Castle Peak flagship at 280 W for WRX80 boards with 8-channel DDR4 memory.
- Socket
- sWRX8
- Launched
- July 14, 2020
- Cores and threads
- 64 and 128
- Default TDP
- 280 W
- Codename
- Castle Peak
- Segment
- Workstation
- Clocks
- 2.7 / 4.2 GHz
AMD Ryzen Threadripper PRO 3995WX specifications
| Cores | 64 |
|---|---|
| Threads | 128 |
| Core architecture | Zen 2 (Castle Peak) |
| Clocks | 2.7 GHz base, up to 4.2 GHz boost |
| Cache | 256 MB L3, 32 MB L2 and 4096 KB L1 |
| Default TDP | 280 W |
| Manufacturing process | TSMC 7 nm FinFET |
| Memory support | DDR4-3200 ECC, 8 channels, up to 2 TB |
| PCI Express | 128 PCIe Gen4 lanes from the CPU |
| Integrated graphics | None (discrete card required) |
| Multiplier | Locked |
| ECC memory | Supported, RDIMM with ECC |
| Package | FC-LGA4094, socket sWRX8 |
| Cooler in the box | None, 280 W workstation heatsink required |
Motherboard and chipset compatibility
AMD Ryzen Threadripper PRO 3995WX needs a motherboard with a sWRX8 socket. The table shows which chipset series accept it.
| Series | Chipsets | Support |
|---|---|---|
| WRX80 workstation | WRX80 | Works out of the box |
Board makers publish a CPU support list for every model. Check it for your exact board before buying. Chipset details for sWRX8.
sWRX8 at a glance
| Type | LGA, 4,094 contacts |
|---|---|
| Package size | 75.4 × 58.5 mm |
| Introduced | July 2020 |
| Memory | DDR4-3200 ECC UDIMM, RDIMM, LRDIMM or 3DS RDIMM, 8 channels, up to 2 TB |
| Cooler mounting holes | Large TR4-SP3 mount (sTRX4, sWRX8, TR4 and SP3 compatible) |
What the Threadripper PRO 3995WX is
The Ryzen Threadripper PRO 3995WX is the sixty four core flagship of the Castle Peak workstation range that AMD listed on July 14 2020 for sWRX8 boards. Its Zen 2 cores run 2.7 GHz base with boost up to 4.2 GHz across 128 threads. Cache is 256 MB of L3 with 32 MB of L2 and 4096 KB of L1, and the TSMC 7 nm FinFET process spreads the load across eight chiplets.
Sixty four cores suit farms in a single socket with massive thread counts for rendering, simulation and software builds. The 2.7 GHz base is the lowest in PRO 3000WX, which costs single thread pace but pays back where all threads stay busy. Eight DDR4 channels with ECC and 128 Gen4 lanes keep the package fed, since memory bandwidth often sets the ceiling before core count.
AMD rates the chip at 280 W default TDP with locked multiplier. The sWRX8 package carries 4094 contacts in a large LGA with carrier frame, and discrete graphics are required. The 90 C maximum operating temperature guides workstation airflow with vendor qualified liquid where sustained all-core runs dominate.
Socket and motherboard compatibility
The 3995WX fits sWRX8 on WRX80 with 8 DDR4 channels. Consumer sTRX4 operation with 4 channels needs the non-PRO AMD Ryzen Threadripper 3990X, so PRO planning centres on WRX80 board choice. Firmware support for Castle Peak PRO must be installed from the maker page. The LGA socket uses three Torx screws in order with the orange carrier.
WRX80 boards for 64 cores are workstation flagships with BMC, ECC validation and multi GPU layouts. Power stages target 280 W sustained with strong VRMs across eight chiplets, so dual EPS and clean case airflow are requirements. Memory population with RDIMM or LRDIMM modules follows one DIMM per channel for full bandwidth to 2 TB, with 3DS RDIMM where validated for density.
The flagship suits studios that keep a single socket busy all day. Buyers who mainly model interactively gain little over 32 cores, while those who queue renders overnight use all 64 cores well. The LGA, PGA and BGA: CPU package types explained guide places sWRX8 LGA handling against desktop sockets for builders new to Threadripper torque procedures.
Memory, PCIe and cooling
DDR4 to DDR4-3200 in 8 channels with ECC gives full bandwidth to 2 TB. Primary slots first per manual, with RDIMM, LRDIMM and 3DS RDIMM validated per board for density. Larger kits need board validation for timing at 3200 MT/s across eight slots. Memory speed past 3200 MT/s helps only where the board qualifies it, since farm stability favours validated speeds.
PCIe from the CPU gives 128 Gen4 lanes for multiple GPUs at by 16 plus Gen4 SSD arrays at by 4 and high speed networking. Chipset lanes add SATA, USB and extra slots. Cooling needs a 280 W workstation liquid unit in most flagship builds, because 64 cores hold high power under all-core rendering even at modest clocks. No box cooler is included.
ECC joins the CPU as a lasting choice. Boards that route ECC with RDIMM correct single bit errors across terabytes of memory, which matters more than headline clocks for long jobs. Population with eight matched large modules beats mixed kits for bandwidth and error coverage in a flagship.
Upgrade paths
On WRX80 the practical steps down are the 32-core AMD Ryzen Threadripper PRO 3975WX for higher clocks at half the threads and the 16-core AMD Ryzen Threadripper PRO 3955WX for interactive work. Many owners gain more from a second GPU or more memory first. Filling 8 channels with large RDIMMs and adding fast NVMe help huge scenes without leaving the socket.
Moving to HEDT on sTRX4 with the AMD Ryzen Threadripper 3990X keeps 64 cores with 4 channels and no PRO management features for desktop oriented builds. For most 3995WX owners the value order is memory to full density, then GPUs, then storage fabric on the same sWRX8 socket.
Used buyers check firmware and cooling first. A WRX80 board that shipped with a 64-core part in 2020 may need no update for another Castle Peak PRO, but a jump to Chagall PRO 5000WX needs a firmware update that adds the new IDs. The twelve core AMD Ryzen Threadripper PRO 3945WX shows the clock focused entry on the same socket for reference.
Frequently asked questions
What socket does the Threadripper PRO 3995WX use?
Socket sWRX8 (LGA 4094) on WRX80 with 8 DDR4 channels. It needs Castle Peak PRO firmware support and does not work in sTRX4 boards.
What memory does the 3995WX use?
DDR4-3200 ECC in 8 channels to 2 TB, with RDIMM, LRDIMM and 3DS RDIMM on most boards. Matched large modules give the best bandwidth for 64 cores.
How many cores does the 3995WX have?
Sixty four cores and 128 threads at 2.7 GHz base and up to 4.2 GHz boost, with 256 MB L3 and a 280 W TDP for flagship throughput work.
Is the 3995WX good for gaming?
It runs farm style rendering and builds with discrete GPUs, but gaming alone does not use 64 cores well. Low base clocks trail smaller PRO parts in lightly threaded tasks, while throughput leads where all threads stay busy.
Sources and verification
- AMD Ryzen Threadripper PRO 3995WX specifications (AMD)
- Socket sWRX8 - 4094 contacts and WRX80 (Wikipedia)
- Zen 2 Castle Peak workstation CPUs (Wikipedia)
Facts last checked against these sources on . Page last edited on .