The ASRock DeskMini 110 gives you one NVMe slot and a 2.5-inch bay

The ASRock DeskMini 110 splits storage between one M.2 NVMe (PCIe 3.0 x4) slot and one 2.5-inch SATA III bay. There’s no second SATA port, so you pick one 2.5-inch drive and that’s it — an NVMe boot drive backed by a SATA SSD is the natural move here.