At the recent FMS 2025 conference, Silicon Motion announced its latest consumer controller product roadmap and showcased its next-generation flagship SSD controller, the industry's first PCIe 6.0 SSD controller solution for client PCs.
Silicon Motion's new client PCIe 6.0 SSD controller, codenamed "Neptune," utilizes a PCIe 6.0 x4 interface, features eight NAND channels, and supports interface speeds up to 4800 MT/s. It is designed to be compatible with next-generation 3D NAND flash memory with over 400 layers. The controller delivers sequential performance exceeding 25GB/s and random performance reaching 3500K IOPS, a significant improvement over the current top-tier client SSDs using the PCIe 5.0 x4 interface.
The "Neptune" controller also features a Separate Command Architecture (SCA), which separates command and address transmission paths within the NAND interface, allowing the controller to process commands and addresses simultaneously rather than sequentially, reducing latency and increasing available bandwidth. However, compared to Silicon Motion's enterprise-grade SM8466 controller, the "Neptune" controller offers lower performance, as it features 16 NAND channels and, thanks to various optimizations, provides stronger sustained performance.
Silicon Motion stated that mass production of the "Neptune" controller chip is planned for 2028, but related SSDs are not expected to appear until 2029-2030. Previously, Silicon Motion founder and CEO Will Kou stated in an interview that PCIe 6.0 SSDs for client PCs are unlikely to arrive before 2030, and that neither AMD nor Intel are currently interested in this feature.
