I recently moved into a new house and had 1 Gbps internet installed. The connection is consistently fast on my phones, TVs, and other devices, with my phone usually reaching around 900 Mbps to 1 Gbps. However, the connection on my PC is extremely unstable when using Ethernet. The Ethernet cable is plugged into the router, and Task Manager frequently shows the network speed dropping to 0 Mbps. Web pages often fail to load or take a very long time.
Nothing appears to be using excessive bandwidth, and I have already restarted the PC and modem, updated Windows, updated the Ethernet adapter drivers, and confirmed that no VPN is active. I also temporarily disabled the Windows firewall, but the problem continues.
Could the Ethernet cable, router port, or network adapter be faulty? I am considering wiping and reinstalling Windows since the PC has not been reset in about six years, but I would prefer to try other troubleshooting steps first.
2 Answers
Make sure the cable is connected to one of the router's LAN ports, not the modem or the router's Internet/WAN port. Since every other device is fast, the issue is probably local to the PC, its cable, or the specific router port. Before wiping Windows, test the PC with another cable and port, and if possible try a USB Ethernet adapter to isolate the built-in network adapter.
Try a different Ethernet cable first, preferably a known-good Cat5e or better cable. Cables can develop faults even if they worked normally a year ago. Also try another LAN port on the router and check whether Windows reports the adapter as connected at 1 Gbps in its connection properties.
Related Questions
Lenovo Thinkpad Stuck In Update Loop Install FilterDriverU2_Reload