USB 3.2 Gen 2x2 vs. USB4
Comparing 2 standards across 5 specifications. 5 key differences identified.
USB 3.2 Gen 2x2, part of the USB 3.2 specification released in September 2017, is the only tier in the 3.2 family that's genuinely new hardware rather than a renamed predecessor -- it doubles Gen 2's 10 Gbit/s by running two lanes simultaneously, reaching 20 Gbit/s, but only over USB-C connectors and cables wired for it.
USB4, released August 2019, is built on Intel's Thunderbolt 3 protocol, donated to USB-IF as the new foundation -- up to 40 Gbit/s, a mandatory USB-C connector, and tunneling that lets a single port carry USB, DisplayPort, and PCIe traffic at once. Thunderbolt 3 compatibility is required; Thunderbolt 4 compatibility is optional for device makers.
Specification Comparison Table
5 Parameters| Parameter / Spec | ||
|---|---|---|
|
Released
|
September 2017 | August 2019 |
|
Max Bandwidth / Data Rate
|
20 (2 lanes x 10 Gbit/s each) Gbit/s | Up to 40 (Gen 3x2) or 20 (Gen 3x1) Gbit/s |
|
Connector Required
|
USB-C only (dual-lane wiring not present in USB-A/B) | USB-C only |
|
Marketing Name
|
USB 20Gbps | — |
|
Protocol Foundation
|
— | Intel Thunderbolt 3 (donated to USB-IF) |