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

Built with a PCI Express® Gen 4 x4 interface, 3D NAND flash, an 8-channel Why couldn't my Transcend PCIe SSD be inserted into the notebook slot?

Eight NVMe SSD slots on a PCIe x16 card Silent operation Add your own ultra-fast SSDs for Mac, Windows, and Linux

pcie gen 4 in gen 3 slot There are four PCI-E slot on the MB The first one supports 16x and so does the third one highlighted in yellow 4

pcie nvme slot LEGEND 960 delivers sequential read and write speed of 7,4006,800MB per second, which is up to 4 times faster than a standard PCIe Gen3 SSD and 13 times faster