I've been troubleshooting a tricky issue with my home network for several days and could use some help. I have two PCs hardwired to the same router: PC 1, my main machine with a 2.5 GbE port, and PC 2, a mini PC with a 1 GbE port. When I run speed tests to a local server (in my country), both PCs hit max speeds, which are 2 Gbps down and 1 Gbps up for PC 1, and 1 Gbps down and up for PC 2. However, when I test to servers in other countries, things get weird—PC 1 has a significant drop in upload speeds, sometimes by as much as 80%, with tests showing only around 200 Mbps compared to PC 2, which comes close to maxing out at 950 Mbps. Download speeds stay pretty consistent across both machines.
I've tried everything I can think of: testing with different ISPs, changing Ethernet cables and ports, swapping routers, and even using different settings for the network interface cards. I tested with multiple browsers, ran diagnostics like traceroutes, updated and downgraded drivers, and even installed a fresh OS on a new SSD only to find that my speeds to foreign servers dropped even more. Interestingly, when I booted into Linux Mint, the Realtek NIC on PC 1 performed much better than the Intel NIC in a Windows environment.
I even switched PC 2 to the same location and setup as PC 1 to rule out connection issues, but the upload speed remains slow for PC 1. I've confirmed that there's no packet loss, and the ping times are similar for both systems. With all this testing, I'm convinced there's something specific affecting PC 1's upload speed to remote servers. Any help would be much appreciated!
1 Answer
Have you tried running openspeedtest specifically for local connections? It might help determine if there's an issue with your local network handling or if the problem is with the upload process itself when dealing with remote servers. Sometimes the routing or the path could cause delays that your local tests wouldn’t show.
I did test both PCs locally with openspeedtest, and PC 2 got max speeds, but PC 1 dropped about -20% on download and -30% on upload. So it looks like the issue might be with PC 1.