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1 week ago
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Published Oct 19, 2026, 2:30 PM EDT
Manuviraj is a tech enthusiast who covers Windows, macOS, and retrocomputing. Drawn to both the logic and the creativity of technology, he’s especially interested in how people interact with tech and the internet every day.
He holds an English Literature degree. His fascination with tech grew alongside a love for speculative worlds: cyberpunk and sci-fi literature shaped the way he thinks about the future of machines and humans sharing space.
Outside the screen, Manuviraj’s world runs on two wheels and good sound. He’s into motorcycling, constantly exploring new music, and tinkering with digital tools just to see what they’re capable of. Whether he’s breaking down complex software topics or diving into niche corners of tech culture, he’s driven by the same thing: figuring out how things work, and how they could work better. You can also read his work on his Substack.
I recently switched ISPs and upgraded my internet connection from 50Mbps to 150Mbps. One of the first things I planned to do was re-download my entire Steam library, which was wiped by an HDD mishap. But something else was in store: I immediately noticed I wasn't getting the advertised speeds for my plan.
My first instinct was to call the ISP, which I did, but they confirmed everything was fine on their end. After about an hour of messing around with my router settings, I realized the problem had been right in front of me this whole time. And what made it clear was a simple Windows status screen.
My PC and router had struck a deal
Which made my connection slower than it should be
An Ethernet-related property most people don't think about is link speed. And it has nothing to do with your incoming internet speed or which plan you're on, which is what most people definitely think about. Instead, it's the speed of the local connection between your PC and the router. Depending on your networking hardware and connection type, it's typically a number like 100Mbps, 1Gbps, 2.5Gbps, etc.
Most people don't have to ever worry about link speed because your computer and the router automatically come to an agreement about it and choose the highest setting supported by both devices. This is called Auto Negotiation.
You can view the auto-negotiated link speed between your PC and the router by opening Control Panel, going to Network and Internet > Network and Sharing Center, and clicking Change adapter settings. Once you're there, right-click on your Ethernet adapter and choose Status. You'll see the link speed listed next to Speed. This screen was what told me the issue lay in my setup: the link speed on my PC was 100Mbps. No wonder my speed test results all ended up under 100Mbps despite my internet plan being 150Mbps.
I use a Cat5e Ethernet cable which supports Gigabit speeds (1.0Gbps), so it was strange that my PC and router had auto-negotiated the link speed to 100Mbps instead of 1.0Gbps. I ruled out software-related issues first, which was mostly just checking my router's settings to see if anything was off.
Then, I confirmed that the Speed & Duplex option was indeed set to auto-negotiate, and not manually defined: Gigabit Ethernet over copper requires auto-negotiation, otherwise it may fail to establish a link or switch to a lower speed/fallback mode. You can check the Speed & Duplex settings by navigating to Device Manager > Network adapters. Right-click on your Ethernet adapter, choose Properties > Advanced, select Speed & Duplex under Property, then pick from the Value menu.
With the above ruled out, I had an inkling that the issue was related to my network hardware.
My Ethernet cable was the culprit
A simple swap instantly restored the link speed
Testing the weak link in your network chain can be slightly tedious: you need to isolate each point of failure, such as the router, the wall sockets, the Ethernet cable, RJ45 ports and connectors, a hub, or a switch. Since my PC is directly connected to the router via the Ethernet cable, the first thing I did was a cable swap with a brand new Cat5e cable. And...it worked. I re-checked the link speed and saw that it was back to 1.0Gbps. A speed test confirmed that my internet speed was on a par with my internet plan, at 150Mbps.
But why did my Cat5e Ethernet cable switch to a link speed of 100Mbps in the first place? I reckon it was because the fault lay in the wires inside the cable. A typical Ethernet cable uses twisted-pair cabling, meaning it has eight copper wires twisted into pairs and running under the plastic casing. Gigabit Ethernet requires all four pairs to work, whereas 100 Mbps manages fine with just two.
Physical trauma, such as stepping on the cable, can damage the internal wiring, causing a gigabit-rated cable to revert to 100 Mbps or lower because one or more twisted-pair wires are damaged. My cable was quite old and had seen its fair share of office chair rolls and being caught between the door while I shut it, making this explanation the most plausible one.
Another common reason behind slow link speeds is using the wrong cable for your network. Most modern Ethernet cables (Cat5e and above) support Gigabit (1000Mbps) link speeds, but Cat5 or earlier cables are rated for 100Mbps and don't handle Gigabit well.
Pick the right Ethernet cable for your setup
Now that I think about it, I could have done one thing differently. I went for the same cable category that I had earlier, and while Cat5e cables are decent, I should ideally have picked a Cat6 or better to future-proof. A Cat6 cable really does make a big difference if you plan to add stuff like NAS, media servers, or CCTV cameras to your home: thanks to its higher 250 MHz bandwidth, which gives you headroom for 10Gbps transfers to a NAS, and its better crosstalk protection, which keeps data clean when several cables run side by side.
