Why is my gigabit Ethernet test stuck around 90 Mbps?

A 100 Mbps Ethernet negotiation commonly produces results near 90–95 Mbps. Check for a damaged/two-pair cable, 100 Mbps port, adapter/dock limit or forced speed setting.

What to check

Link speed; cable category/condition; port and adapter capability.

When to get help from a person

Escalate if router port will not negotiate gigabit with known-good equipment.

Show the technical detail
On a managed Wi-Fi plan

Inspect gateway port negotiation where telemetry allows; retest with known-good Cat5e+ cable and gigabit adapter.

On another provider's router

Same physical-layer checks apply to any ISP.

What to be careful of

Do not attribute a 100 Mbps link ceiling to Wi‑Fi.

Where this comes from: Official · see the original source ↗ · Draft—technical review · checked 17 August 2026

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