Speed requirement: 4Mbps or below
Speed requirement: 4Mbps or below
I've been using this computer and my internet connection has been stable since 2014. I've only experienced one problem before. Last year I swapped the Ethernet cable for a new one, and everything worked fine. I haven't updated any software or changed system settings. Now I'm facing the same issue again—it's really frustrating. I'm consistently getting around 41Mbps upload speeds, but downloads are now only about 4Mbps or less, regardless of what I do. I've tried everything possible: 1) swapped to a cat6 cable, 2) reset router and modem multiple times, 3) changed ports on the router, 4) connected directly to the modem without using the router, 5) reinstalled drivers, 6) booted in safe mode, 7) performed a clean BIOS reset, 8) reinstalled drivers manually, and 9) tried a different port. I even used the Killer port on my motherboard, which improved performance somewhat but still only provided around 200Mbps download most of the time. It fluctuates wildly, sometimes over 100 Mbps, other times barely above 300. After all these attempts, I'm left wondering what's happening. My wireless adapter seems to handle about 600Mbps out of its 1Gbps capacity, yet Ethernet is completely dead. It's really annoying because I expected the usual 980Mbps download speed. I've spent around $800 on a high-quality modem and router, both functioning perfectly. I suspect the issue might be with the ports themselves, but I haven't tried anything else. My best guess is that they could be aging, or perhaps the cable was the real problem—though it worked for months after replacement. I'm not sure if a fresh OS installation would help, but I'm not sure what's causing this sudden drop in performance. The fact that upload speeds are improving while downloads stay stuck at low levels is really puzzling.
The Bad NIC sounds like it might need a different setup. Would you like to use another person's laptop for testing?
I've already checked the other PCs and devices, they seem normal. The problem appears to be only with one port on the motherboard, which is functioning otherwise but not as well. It's strange that uploading works fine at full speed, yet downloads stall around 4Mbps or less through that port. I suspect the port might be aging or damaged, though I've ruled that out before—especially since my other computers are still working and their Ethernet ports are okay. There was a similar issue after upgrading my ISP connection, which resolved itself with a new cable. It's possible some setting or option triggered it, but it's unlikely. I plan to try a clean Windows installation when possible to confirm if the problem continues.
I planned to start from a USB thumb drive into Windows without reinstalling on top, but trying it for Linux would be a good check if the problem continues after a fresh Windows setup. Great idea you had in mind! It just came to my attention later.