Another thing to check would be to use ethtool to see what speed the raspberry pi ethernet port is reaching with your router. This wasn't on a pi, but it'll lo

Another thing to check would be to use ethtool to see what speed the raspberry pi ethernet port is reaching with your router. This wasn't on a pi, but it'll look similar. Look at the Speed: line mostly, it'll say either 100MBit or 1000MBit depending on your router (some still only have 100MBit switches). Also look for Duplex: Full, I've had sometimes a config get set badly where it'll be half duplex and cause speed issues, usually due to a bad cable initially causing errors and bad autodetection. > % sudo ethtool enp4s0 Settings for enp4s0: Supported ports: [ TP ] Supported link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Supported pause frame use: Symmetric Supports auto-negotiation: Yes Supported FEC modes: Not reported Advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Advertised pause frame use: Symmetric Advertised auto-negotiation: Yes Advertised FEC modes: Not reported Speed: 1000Mb/s Duplex: Full Port: Twisted Pair PHYAD: 1 Transceiver: internal Auto-negotiation: on MDI-X: off (auto) Supports Wake-on: pumbg Wake-on: g Current message level: 0x00000007 (7) drv probe link Link detected: yes