What is USB 3.1 Gen 2?
USB 3.1 Gen 2 is the USB speed tier that runs at 10 Gbps, double the 5 Gbps of USB 3.0. Its marketing name is SuperSpeed USB 10Gbps. It arrived with the USB 3.1 specification, and when USB 3.2 came out the same 10 Gbps mode was renamed USB 3.2 Gen 2. Nothing changed technically: it's one speed with two names, which is why spec sheets get confusing.
Untangling the USB 3.x names
| Speed | Original name | USB 3.1 name | USB 3.2 name | Marketing name |
|---|---|---|---|---|
| 5 Gbps | USB 3.0 | USB 3.1 Gen 1 | USB 3.2 Gen 1 | SuperSpeed USB 5Gbps |
| 10 Gbps | None | USB 3.1 Gen 2 | USB 3.2 Gen 2 | SuperSpeed USB 10Gbps |
| 20 Gbps | None | None | USB 3.2 Gen 2x2 | SuperSpeed USB 20Gbps |
USB4 superseded these with 20 and 40 Gbps modes (and faster in later versions) over USB-C only. A USB4 or Thunderbolt port can still run 10 Gbps USB devices.
Connectors, cables and markings
- Connectors: 10 Gbps ports come as USB-C or Type-A. USB-C is only the connector shape; a USB-C port can be anything from USB 2.0 to USB4, so check the spec.
- Markings: look for an SS 10 or 10Gbps logo next to the port, or check the motherboard or laptop manual. Port color isn't standardized for 10 Gbps, so don't rely on it.
- Cables: you need a cable rated for 10 Gbps. A USB 2.0 or 5 Gbps cable limits the link to the lower speed.
- Compatibility: it's backward compatible. A 10 Gbps drive on a 5 Gbps or USB 2.0 port works at the slower port's speed.
Where it's used
10 Gbps USB suits external SSDs, docking stations and fast card readers. When a fast external SSD copies slowly, check that the drive, the cable and the port all support 10 Gbps.
For the CompTIA A+ exam
Core 1 (220-1201) objective 3.2 lists USB 2.0, USB 3.0 and USB-C among cables and connectors, and objective 1.2 covers USB connection methods for mobile devices. USB 3.1 Gen 2 isn't named, but you should be able to read the renamed versions: 5 Gbps is USB 3.0, USB 3.1 Gen 1 or USB 3.2 Gen 1, and 10 Gbps is USB 3.1 Gen 2 or USB 3.2 Gen 2.