Answer: at a fixed bandwidth, a longer cable needs thicker conductors (a smaller AWG number) to keep the same signal margin — but copper has a hard practical limit.
- Quoting a 5 m Ultra High Speed cable and a 20 m one at the same price usually means one of them is not really that tier.
- Beyond the copper limit, adding thickness stops helping; an active optical cable is the correct answer.
- Ask for the tested distance at the target resolution, per model.