What is USB4?

What it is

USB-C is only the shape of the plug. What a port or cable can do depends on the standard behind it, and USB4 is the one that brings in the Thunderbolt-based protocol. Not every USB4 port runs at the same top speed, so check the rating on the laptop and the dock.

• One cable: a laptop can charge, drive a monitor and talk to a drive through a single USB4 connection.
• Same plug, different capability: two USB-C ports side by side can differ widely. One may charge only, another may handle video, another may run USB4.
• Cable quality: cables are rated for speed and for power. The wrong cable can limit speed, drop the display or charge a laptop slowly.

USB4 is closely tied to Thunderbolt, which Intel developed. Our Intel page has more on the company.

Why it matters to a business

• Fewer cables on desks: one connection to a dock replaces separate power, video and network cables.
• Mystery faults: a flickering monitor or a slow drive is often a weak cable or the wrong port, not a broken device.
• Purchasing: a laptop specification that just says USB-C leaves out what matters. Ask which standard each port supports.
• Spare cables: a drawer of unlabeled cables invites mismatches. Keep rated ones and mark them.

How this shows up in our work

Under managed IT we supply the whole desk: laptop, dock, monitors, keyboard, mouse, headset and the cables between them. Keeping that kit standard is what lets a replacement laptop work at a desk the same way the old one did.

Learn more

• USB4 on WikipediaAn overview of the standard, its versions and its link to Thunderbolt.
• USB Implementers ForumThe group that maintains USB standards, with logos and specifications.
• Thunderbolt on WikipediaUseful background for readers comparing USB4 with Thunderbolt.