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What is USB4?

2023-01-25 02:05:27



When it comes to connecting devices and transferring data, USB (Universal Serial Bus) cables have become an essential part of our daily lives. As technology continues to evolve, the demand for faster and more efficient data transfer has led to the development of the USB4 standard. This latest version of USB offers significant advancements in terms of speed, connectivity, and flexibility, making it a game-changer for both personal and professional use.

Speed and Efficiency

One of the most notable features of USB4 is its speed. This new standard offers a minimum transfer speed of 20 Gbps and can support up to 40 Gbps, which is significantly faster than its predecessor, USB 3.2. With this speed, USB4 allows for faster file transfers, smoother streaming, and improved overall performance when connecting multiple devices. Additionally, USB4's transfer speed also enables support for high-resolution monitors and external storage devices that require high bandwidth.

Another feature that contributes to USB4's efficiency is its support for tunneling of DisplayPort and PCI Express. This allows for a more efficient use of bandwidth and enables multiple devices to share the same high-speed link, dynamically allocating the necessary amount of bandwidth to each device based on their specific needs.

USB4 vs Thunderbolt 4

The development of USB4 was based on the Thunderbolt 3 protocol, which was donated by Intel to the USB Implementers Forum (USB-IF). This means that USB4 unifies USB and Thunderbolt protocols for the first time, making it possible to share a single high-speed link with multiple types of devices. This feature sets USB4 apart from Thunderbolt 4, which is more geared towards professional users and high-end devices, whereas USB4 is more versatile and can be used for both personal and professional use.

USB4 version 2.0

In 2021, the USB-IF introduced USB4 version 2.0, which further improves upon the capabilities of the original USB4 standard. This version requires USB-C connectors and support for USB Power Delivery (USB PD), allowing for faster charging and power delivery to devices. Furthermore, USB4 version 2.0 supports a maximum of four 1K monitors at a 120Hz refresh rate, two 4K monitors at 120Hz, and one 8K monitor at 30Hz, making it a suitable option for both home and office use.

Dynamic Bandwidth Allocation and Alt Mode

Another important feature of USB4 is its support for dynamic bandwidth allocation. This allows for multiple devices to be connected to a single USB4 port and for the necessary amount of bandwidth to be allocated to each device based on their specific needs. This feature is especially useful when connecting devices such as a PC, monitor, and external SSD, where each device requires a different amount of bandwidth.

Additionally, USB4 also supports Alt Mode, which allows for the connection of other protocols such as HDMI, DisplayPort, and Thunderbolt, without the need for additional adapters or cables. This feature makes USB4 more versatile and allows for easy connectivity to a wide range of devices, including monitors, TVs, and other accessories.


Overall, USB4 is a significant advancement in the world of data transfer and connectivity. Its faster transfer speeds, dynamic bandwidth allocation, and support for other protocols make it a versatile and efficient option for both personal and professional use. As more and more devices and accessories adopt this new standard, USB4 is set to become the new norm for data transfer and connectivity.