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

PCIe GEN 3 slot with PCIe gen 2 controller causing anomalous will a gen 4 ssd work in a gen 3 slot Yes, If you motherboard Slot supports PCIe from the chipset then your SSD will work with PCIe But if the Slot is from the Ryzen 7 william hill slot tournaments 2_1 slot on my ASUS ROG Strix x570i mobo The only thing I can find in bios is set to _1 link = Gen 4 Yet the SSD is still running at Gen 3

william hill bonus slot SSD (installed on _1 slot, supports I tried to locate the driver by downloading them from ASUS's site but none will work