I've got PC and laptop, both connected with wire to switch witch supports 1gb/s transfer. My download speed from Internet is about 800mb/s. On laptop is nvme type disk, on pc I've got SSD sata, Ubuntu 20.04 on both. When I'm downloading files using rsync download speed is about 20mb/s. I was hoping for maximum speed and certainly not so low ... is it possible?
ethtool eth0
(change eth0 to the name of your wired network deviceifconfig
to list devices/names). Also how are you measuring the speed and what command are you using? What are you transferring to get the measurement, lots of files, one big file?