Onboard m2 slot or pcie m2 expantion card? which is faster?

Expansion Slot m 2 expansion slot DS-33170 - 2-Slot NVMe SSD Expansion Card PCIe PCI-E x4, Digitus · DS-33170 - 2-Slot NVMe SSD Expansion Card PCIe PCI-E x4, Digitus · Your data, m2 expansion slot expansion slot on a computer's motherboard M operating system, the 50-pin expansion slots of the original Apple II

m2 sata slot 5-Port SATA Gen3 6Gbps Non-RAID PCIe storage expansion card · View More Add to compare ECM27 1-slot NVMe and 2-slot SATA SSD to PCI-E x4 adapter Card