Z390: SSDs and disabed SATA ports - ASRock Forums

Compare SSD , mSATA, , SATA Express - m 2 sata slot on motherboard Some motherboards will only have one slot that can run at NVMe PCIe bandwidth, whereas others may be restricted to using SATA bandwidth m2 slot pc SATA: This option uses the AHCI driver and routes to a SATA port via the connector It is slow, but widely compatible AHCI: Advanced Host Controller

m2 sata vs nvme slot 2 drives aren't connected to a motherboard via a cable, they're instead plugged directly into the motherboard using a dedicated connector