After seeing that my wireless speeds were much faster than the speeds I was getting over Ethernet, I decided to invest in some new cables. I didn’t know it before, but I saw while I was changing them out that my current cables were Cat 5e. While putting my network together, I had just been grabbing whatever cables I could find in my scrap drawers. Now I have Cat 8 cables and my speeds jumped from 7MB/s to an average of over 40MB/s. It’s a much bigger improvement than I expected, especially for such a small investment.
This. I’ve had issues at work while imaging classroom computers where some would finish in ~30 minutes and a few would need hours. All of the computers used Cat6 cables. This being a classroom, and students being absolute wankbags, they kept yanking the computers and kicking the cables, so the wires came loose from the plugs. I later used ethtool to debug the slow computers – the switch would only allow 10baseT link modes.