NVM Express

2 SSD, the advantage is size and convenience However, the NVMe protocol for interfacing with flash based storage over PCI Express is far

There are two types of SSDs: SATA and NVMe SATA uses an older interface with one designed around hard drives while NVMe is designed for flash memory

nvme m2 slot Explaining the Difference Between SSD NVMe and M2 SATA and mSATA How-FixIT•

nvme gen 4 in gen 3 slot 2 standard contains variants with up to four PCIe lanes, one SATA 6 Gbs and or one USB port So it is possible to connect PCIe as well as SATA SSDs