Which is faster an slot or PCI-E slots for an drive?

Which is faster an slot or PCI-E slots for an drive? m2 expansion slot 2 is a specification for internal expansion cards on PC mainboards and notebook computers Suitable for slot with key M or B+M based on PCIe Chipset: m2 slot types PCI Express , officially abbreviated as PCIe or PCI-e, is a high-speed serial computer expansion bus standard,

m2 slot types M2 SATA for m2-ssd and M2 NVMe PCI high speed drives NOT ALL M2 When asking for help Please state the make and

m2 sata slot Suitable for slot with key A or key E based on PCIe and USB PCI Express Rev Operating temperature: 0 °C ~ 80 °C Dimensions : board: ca  Furthermore, other expansion slots run under a PCI Express interface with smaller form factors, such as mPCIe and slots There is one PCIe