PCIe Gen 4: What is it Good For?

PCIEx16 drops to x 8 when M2 SSD is installed??? can i put a gen 4 m 2 in a gen 3 slot What is the difference between Gen4 and Gen3? Why is there such a large price difference? PCIe Gen4 is the fourth generation of the PCI Express specification can i put a gen 4 m2 in a gen 3 slot PCIe 4 is backwards compatible with gen 3, 2 & 1, and you will get A good quality pcie 4 drive in a pcie 3 slot will be near

can i put pcie x4 in x16 slot Good idea I think the best idea is to get pcie x 4 if building today