PCIe X16 vs X8 with 4 x Titan V GPUs for Machine Learning

What is PCIe x16 Slot pcie slot x16 Will a wifi card fit into a pci-e x16 slot? pcie x 16 slot A x8 card will work in an x1 slot, but will be limited to x1 speeds A x8 card will also work fine in a x4 slot It will be limited to x4 speeds

pcie x1 slot function IPCIE16XD11 is Multiple SFF-8654 x4 to PCIe x16 Slot Expansion with Broadcom MegaRAID 9560-16i, 9560-8i, 9580-8i8e, 9500-16i, 9500-8i,