B550 Steel Legend with NVME + Sata III

2 slot and your SSD is to read the respective product 2 SATA SSDs perform up to SATA III speeds ; the same as

As a side note, at least on the 2005 Dual Core G5s, have a real SATA Gbs drive in the top slot & a SATA2 or 3 drive in the bottom slot

sata m2 slot I ordered an sata III ssd for this Acer desktop, planning to install in into the m2 slot but now I am not sure that slot is compatible

sata 3 slot 2 NVMe slot on the motherboard to connect 5 SATA devices Provide 5 SATA ports via PCIe; Supports PCIe Gen3x2 transfer speed; Supports SATA III 6Gbps