What is the difference between PCIe Gen 3 and PCIe Gen 4?

installing Gen4 NVME on a Gen3 Motherboard pcie gen 4 in gen 3 slot Zen 3 # of CPU PCIe® Native PCIe® Lanes : 24 , 20 Additional Usable PCIe Lanes from Motherboard X570 16x Gen 4 X470 2x Gen 3, 8x Gen pcie 2 slot 1y ago Yes The SSD I have should have speeds of about 4500-5000MBs on PCIe gen4 Although I did recently re-test it and write speed was

pcie 40 in 30 slot Testing and installing a Gen4 NVME SSD on a Gen3 Motherboard This includes Unboxing