Thunderbolt 5 vs Thunderbolt 4 vs USB4 vs USB-C: which dock can your port use?

USB-C is the plug, not the feature list

USB-C names the connector shape. USB-IF separates it from data speed, display output and charging, so a USB-C port can be anything from a slow data port to a full Thunderbolt 5 port. Look for the lightning-bolt icon or the port name in your laptop’s spec sheet.

For a plain USB-C port, check two things in the manual: DisplayPort Alt Mode (for a monitor) and USB Power Delivery (for charging through the dock). Without Alt Mode, only a DisplayLink dock can add a monitor.

Thunderbolt 4: the safe baseline for a one-cable desk

Intel’s Thunderbolt 4 certification requires 40Gb/s, support for two 4K displays or one 8K display, and laptop charging on at least one port. Any Thunderbolt 4 dock, such as the CalDigit TS4, can use all of that.

Thunderbolt 5: more video bandwidth and charging

Intel rates Thunderbolt 5 at 80Gb/s in both directions. Its Bandwidth Boost raises one direction to 120Gb/s, leaving 40Gb/s the other way, when a setup needs heavy video. Intel’s minimum PC requirements list dual 6K displays and laptop charging up to 140W, with up to 240W available on some devices.

A Thunderbolt 5 dock on a Thunderbolt 4 laptop runs at Thunderbolt 4 speed. Buy one for a Thunderbolt 5 laptop, or for the dock’s own charging and networking features.

USB4: close to Thunderbolt, but check the details

USB4 runs at up to 40Gb/s, and USB4 Version 2.0 adds 80Gb/s with an optional 120Gb/s mode in one direction for displays. USB-IF requires USB4 hosts and hubs to support DisplayPort tunneling.

Some Thunderbolt docks need PCIe tunneling, which not every USB4 laptop provides. CalDigit, for example, requires it for the TS5 Plus on USB4 hosts. Check the dock maker’s compatibility notes for USB4 before buying.