Types of PCIe Slots PCle Lanes

4x is overkill, you could handle 8 NICS on that but I've never seen a 2x slot so that's why they're using 4x Presumably they make 4-port

The NVMe PCIe card allows you add PCI-e NVMe SSD to your motherboard without slot, perfect solution for PC upgraded Up to 3200+ MB

pcie 8x slot this mobo has three pci-e slots physically 1x16lanes ,2x1line What i found, the x16 slot is supporting only one pcie line according to

pcie slot x16 x1, x2, x4, x8, x16 PCIe Gen 3 bandwidth, 1 GBs, 2 GBs, 4 GBs, 8 GBs, 16 GB How to Choose an SSD: SATA, ”, NVMe, , PCIe, Explained So you want