The original post: /r/homenetworking by /u/Dmitry52361 on 2025-03-28 22:56:03.
Hello, I hope you guys are doing well.
My situation is as follows: we upgraded our internet from 150 Mbps to fiber 1.5 Gbps. My 5-year-old PC is connected with an Ethernet cable (Cat6) that I crimped with my brother, and the cable runs through the walls. I’ve been trying to solve my problem since Monday because when I do a speed test, I only get 90 Mbps, while the modem shows 1800 Mbps.
Solutions I’ve tried:
- I set the Ethernet settings to “1 Gbps full” -> It worked for 5 minutes on the first day, then stopped working.
- I bought another Cat6 cable to check if my cable was faulty -> The new cable works, and I get 900 Mbps.
- I bought a cable tester to check if my homemade cable was missing a pair -> It initially showed only 6 lights, so I redid the connections on one end. After testing it again, it showed all 8 lights, so my cable is supposed to work.
After that, I tested it again on my main PC, but I still only got 90 Mbps. However, when I tested the same cable on a different Dell PC, it showed 900 Mbps.
I’m really stuck because I would like to keep the cable that runs through the walls, but I don’t know why it’s not working properly. The cable itself isn’t broken because it works on the other desktop, and my PC’s network card is fine because it works with the new cable. I also tried updating some drivers.
It’s as if my main PC is capping a certain type of Ethernet cable differently than my Dell desktop.
I hope you guys can help me. Thanks!