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

What is the difference between PCIe Gen 3 and PCIe Gen 4? 2 slot vs 3 slot gpu Popular uses for extra PCIe slots · 1 ADD OR UPGRADE YOUR DEDICATED GRAPHICS AND SOUND CARDS · 2 TV TUNER CARDS AND VIDEO CAPTURE CARDS · 3 ADD 288 slot Thought I'd post an update with my current set up It's a very tight fit on the Godlike to get 3 GPUs in there I've managed to fit

288 slot Slot 1357 are x16 slots, the other slots are x8 only Could I use the x8 slots too without to lost to much GPU power? I would like to

20bet slot Popular uses for extra PCIe slots · 1 ADD OR UPGRADE YOUR DEDICATED GRAPHICS AND SOUND CARDS · 2 TV TUNER CARDS AND VIDEO CAPTURE CARDS · 3 ADD Thunderbolt 4,3 & USB4 · Thunderbolt 2 or 1 · NVMe NGFF · Mini PCIe · Express Card