The Quartz64 is a new single-board computer (SBC) from Pine64. The Raspberry Pi alternative runs on a Rockchip RK3566 SoC and has a PCIe slot, among other features.
https://www.notebookcheck.net/Quartz64-Pine64-launches-an-alternative-to-the-Raspberry-Pi-with-PCIe-expansion.521671.0.html