USB 3.2 and 3.1 Explained: What’s Gen 1, Gen 2 and Gen 2×2?
USB 4 may be the latest and fastest generation, but the most common USB ports on PCs and peripherals, specifically USB 3.2 or USB 3.1 or 3.0, have a “3” in their version number. If you’re looking at the spec sheet, you’ll also see a generation number after USB 3.2 or 3.1. For example, USB 3.2 Gen 1, USB 3.2 Gen 2, and even USB 3.2 Gen 2×2. Yet some ports with different version numbers are actually the same speed! Still confused?
Luckily, once you understand all the confusing decimal numbers and generation numbers, it’s easy to determine what speeds you can expect from your USB ports, cables, and devices. It is enough to know the terminology outlined below.
USB version | speed | alias | Connector type | Same as |
---|---|---|---|---|
USB 3.2 Generation 1 | 5Gbps | super speed usb | Type A, Type C, Type B, Micro | USB 3.1 Gen1, USB 3.0 |
USB 3.2 Gen2/Gen2x1 | 10Gbps | SuperSpeed+ USB 10Gbps | type A, type C | USB 3.1 Generation 2 |
USB 3.2 Gen 2×2 | 20Gbps | SuperSpeed+ USB 20Gbps | type C | none |
USB 3.1 Generation 1 | 5Gbps | super speed usb | Type A, Type C, Type B, Micro | USB 3.2 Gen1, USB 3.0 |
USB 3.1 Generation 2 | 10Gbps | SuperSpeed+ USB 10Gbps | type A, type C | USB 3.2 Generation 2 |
USB3.0 | 5Gbps | super speed usb | Type A, Type C, Type B, Micro | USB 3.1 Gen 1, USB 3.2 Gen 1 |
USB 3.2 vs. USB 3.1 and USB 3.0: What’s the difference?
USB 3.0, USB 3.1 Gen 1 and USB 3.2 Gen 1 are all compatible and run at 5 Gbps whereas USB 3.1 Gen 2 and USB 3.2 Gen 2 are the same and run at 10 Gbps hence the version number is confusing and doesn’t make much sense. .
In fact, the USB-IF (USB Implementers Forum), which creates the standard, recommends that manufacturers not use these version numbers at all, instead listing their products as either SuperSpeed, SuperSpeed 10 Gbps, or SuperSpeed. I have said several times that I would like to 20 Gbps, or simply as USB 5 Gbps, USB 10 Gbps, and USB 20 Gbps.
Many vendors skip this if you are a vendor and have paid to have your product officially certified by the USB-IF, but your organization may want you to use a set of It even has a logo.
However, despite the desire of the USB-IF, I still see most PC vendors listing their ports as USB 3.2 or USB 3.1. The spec sheet may not list a generation number, but if not, it should be assumed to be Generation 1 (5 Gbps).
The reason there are different USB 3.x version numbers is because the numbers were repeated with each speed increase. In 2008, the USB 3.0 standard was announced, making USB up to 5 Gbps. This is a huge leap from USB 2.0’s 480 Mbps speed, which has been as fast as USB for many years. In fact, even today, most USB ports and products do not exceed 5 Gbps, nor do they need to. Many peripherals don’t even need to go beyond USB 2.0.
In 2013, the USB-IF announced that it was pushing USB up to 10 Gbps, and in doing so changed the version numbers of all USB 3.x products. So USB 3.0 (5 Gbps) became USB 3.1 Gen 1 and the new 10 Gbps speed became USB 3.1 Gen 2.
In 2017, the organization rolled out 20 Gbps speeds for USB 3.x devices. To celebrate the new speeds, the version numbers for all speeds have changed, so 5 Gbps speeds became USB 3.2 Gen 1, 10 Gbps speeds became USB 3.2 Gen 2, and 20 Gbps speeds became USB 3.2 Gen 2×2. I was.
The 20 Gbps speed is called USB 3.2 Gen 2×2 because it uses two 10 Gbps lanes to provide 20 Gbps speed. Would it be less confusing if they called it USB 3.2 Gen 3?
There is also a lesser used version called USB 3.2 Gen 1×2. That’s 10 Gbps, about the same as USB 3.2 Gen 2. The difference is that USB 3.2 Gen 2 has one 10 Gbps data lane, while USB 3.2 Gen 1×2 has two 5 Gbps lanes for a total of 10 Gbps. As an end user it shouldn’t matter, but you may see the term USB 3.2 Gen 1×2.
What kind of connector do USB 3.2 and USB 3.1 use?
Both 5 Gbps and 10 Gbps speeds are available with USB Type-A or USB Type-C connectors. A USB Type-A port has a traditional rectangular connector that can only be inserted one way. The USB Type-C port is smaller, oval and reversible. Despite the fact that USB Type-C is very common in laptops and phones, many modern desktops don’t even have a single USB Type-C port.
Less commonly, there are also USB 3.x cables with Type-B connectors. This is a square connector primarily used to connect to printers and USB hubs.
There are also some SuperSpeed micro USB connectors. However, these SuperSpeed Type-B and micro USB connectors are larger than regular Type-B and micro USB connectors and are not backwards compatible.
So if you want to know what kind of wire or adapter a port needs, you can’t tell just by the version number. A USB 3.2 Gen 1 or USB 3.2 Gen 2 port, or USB 3.1 equivalent, can have either type of connector.
But if you’re using USB 3.2 Gen 2×2 (20 Gbps), you’re definitely using USB Type-C. Type-A ports are capped at 10 Gbps. Also, although rare, USB 3.2 Gen 1×2 (also 10 Gbps) can only use Type-C.
What color are the USB 3.2 / USB 3.1 ports?
The USB-IF does not mandate that USB ports must be a specific color. However, blue ports are usually 5 Gbps, which means they are SuperSpeed USB (also known as USB 3.2 Gen 1, USB 3.1 Gen 1 or USB 3.0). Some manufacturers now feature SuperSpeed 10 Gbps USB (also known as USB 3.2 Gen 2 or USB 3.1 Gen 2) using the red USB port.
However, it’s also possible that the port is just black, which doesn’t indicate anything. The best way to determine speed is to check your device’s spec sheet, whether it’s a USB hub, SSD, or motherboard.
What cable do I need for USB 3.2 / USB 3.1?
Like all USBs, USB 3.2 and USB 3.1 are backward compatible with older USB standards. So when you use a USB 2.0 device or cable and plug it into a USB 3.2 port, it will connect at the speed of the slowest link in the chain (480 Mbps in this case).
If you have a USB 3.2 Gen 2 port and want to take advantage of its 10 Gbps speed, you need a cable that supports 10 Gbps (which could be USB 3.2 Gen 2 or USB 3.1 Gen 2) and a peripheral with the same capabilities. please look for it. If you want to achieve 20 Gbps speed, all three of your ports, peripherals, and cables must support that speed.
What can you do with USB 3.2 or USB 3.1?
USB 3.2 Gen 1 and USB 3.1 Gen 1 operate at speeds up to 5 Gbps, which by itself exceeds the speeds most peripherals require on their own. Wired mice and keyboards, even those with high polling rates, do not exceed the 480 Mbps limit of USB 2.0. However, some of the best webcams require a USB 3.2/3.1/3.0 connection, especially if they offer 30 fps at 2K or 4K resolution.
If you’re using a USB hub, you’ll need a connection of at least 5 Gbps. This is because all peripherals connected to that hub share that bandwidth. So if you have a mouse, keyboard and webcam all connected to the same hub, you definitely want at least the 5 Gbps provided by USB 3.2 Gen 1 / USB 3.1 Gen 1.
Monitors or docking stations that use DisplayLink technology, which allows a computer to output video over a standard USB Type-A port, often require speeds of 5 Gbps.
Finally, and perhaps most importantly, your external SSDs and hard drives should have at least USB 3.2 / 3.1 / 3.0 speeds. The fastest external SSDs or SSD enclosures can run at USB 3.2 Gen 2 (10 Gbps) or USB 3.2 Gen 2×2 (20 Gbps), but 10 Gbps speeds are much more common and cheaper.
A quick search on Amazon turned up M.2 NVMe. $68 for USB 3.2 Gen 2×2 Enclosure (opens in new tab) When USB 3.2 Gen 2 Enclosure for just $28 (opens in new tab).
How much power do USB 3.2 and USB 3.1 provide?
The USB 3.2 / USB 3.1 / USB 3.0 standard only specs at 5 volts and 900ma, totaling 4.5 watts which is not very impressive. This is far better than USB 2.0, which caps at 2.5 watts, but not enough to quickly charge the latest smartphones and tablets. Also consider that an individual USB 3.2, Type A port on your laptop or desktop may not be able to deliver that much power, as 4.5 watts is the maximum.
standard | port type | max wattage | max ampere | bolt |
---|---|---|---|---|
USB3.2/3.1/3.0 | USB-A, USB-B | 4.5W | 900mA | 5V |
USB Power Delivery (PD) | USB-C only | 240W | 5A | 5V, 9V, 15V, 20V, 28V, 36V, 48V |
USB battery charging (BC) | USB-A, USB-C | 7.5W | 1.5A | 5V |
USB-C (non-PD) | USB-C | 15W | 3A | 5V |
USB2.0 | USB-A, USB-B, micro-USB | 2.5W | 500mA | 5V |
However, it’s important to remember that the charging standard a port supports and the USB version number are not necessarily related. Many chargers and hubs use charging standards well beyond the limits of USB 2.0 or USB 3. Those using USB Battery Charging (USB BC) can deliver up to 7.5 Watts on a Type A port. And then there are third-party standards like Qualcomm Quick Charge that go above 18 watts.
If you’re using a USB Type-C cable and port, your charger/host device may support USB Power Delivery (USB PD), which can be as high as 240 watts. However, wattage has nothing to do with data speed, as USB 2.0 ports may be powered and USB 3.2 ports may not.
Video over USB 3.2 / USB 3.1
Technically speaking, neither USB 3.2 nor USB 3.1 alone can deliver video. DisplayLink technology allows video to be converted and compressed into USB data for transmission to specially capable hubs or portable monitors. However, very few people use DisplayLink devices today.
Many of the best ultrabooks and best graphics cards have a USB Type-C port that supports “alt mode”. This means that USB cables and ports can deliver data using protocols that are not part of the USB specification. Often that protocol is DisplayPort 1.2, 1.3, or 1.4, which allows you to connect your computer to a monitor or TV. However, just because a port supports USB 3.2 or USB 3.2 Gen 2×2 does not necessarily mean it supports alt mode.