SiFive's HiFive Unmatched mini-ITX platform is designed for DiY developers. It comes with a 5-core RISC-V processor complemented by 8 GB of onboard DDR4 RAM. USers can add an NVMe SSD, a wireless card and a dGPU or any other PCIe Gen 3 X8 expansion card. The platform is compatible with many popular Linux distributions and will soon be up for pre-orders at US$665.
https://www.notebookcheck.net/SiFive-readies-the-HiFive-Unmatched-world-s-first-RISC-V-based-desktop-PC-platform.500607.0.html