5 Myths About Ethernet Cables That Are Costing You Performance

You have probably heard it before: just plug in an Ethernet cable and your network problems disappear. While a wired connection really is more reliable than Wi-Fi in most situations, the world of Ethernet cables is cluttered with half-truths that lead people to waste money, settle for less than their connection can deliver, or misdiagnose real problems. Let's clear the air.

Myth 1: Any cable is as good as any other cable.

This is probably the most expensive misconception in home networking. Ethernet cables are rated in categories — Cat 5e, Cat 6, Cat 6A, Cat 7, Cat 8, and beyond — and those ratings exist for a reason. Each category supports different maximum speeds and bandwidth over different distances. Running a Cat 5e cable to a 2.5 Gbps network port will bottleneck your speed, full stop. The cable is the weakest link, and if you bought your current cables years ago without checking the category, there is a real chance they are holding you back.

Myth 2: A higher category cable always means better performance in your setup.

The flip side is equally misleading. Buying Cat 8 cable for a home network running a standard 1 Gbps router is overkill that delivers zero real-world benefit. Cat 8 is engineered for data centres and very short runs at extremely high speeds. Its shielded construction can actually introduce grounding issues in environments not designed for it. Match the cable category to your actual hardware and use case, not to the highest number on the shelf.

Myth 3: Cable length does not matter much.

Ethernet standards specify a maximum run of 100 metres for most twisted-pair cables before signal degradation becomes a problem. Most home users will never hit that limit, but in larger offices or buildings where cables are routed through walls and ceilings, runs can get surprisingly long. Exceeding the rated length without a switch or repeater in between is a reliable recipe for dropped packets and unstable connections.

Myth 4: Shielded cables are always better for homes.

Shielded twisted-pair cables (STP) are designed for environments with heavy electromagnetic interference, like factory floors or server rooms. In a typical home or small office, unshielded twisted-pair (UTP) cable performs just as well and is easier to terminate and route. Shielded cable requires a properly grounded infrastructure to work as intended — without it, the shield can actually act as an antenna and make interference worse.

Myth 5: Once a cable is installed, you never need to think about it again.

Physical cables degrade. Repeated bending, crushing under furniture, UV exposure near windows, and poor-quality connectors all erode performance over time. If your wired connection has become unreliable and your router and hardware check out fine, the cable itself is a legitimate suspect worth testing or replacing.

If you are building or upgrading a wired home or small-office network, pairing the right cable category with quality hardware — the kind of gear covered in the ShazConnect section of this site — is the foundation everything else rests on. Get this layer right and the rest of your network has a fighting chance.