USB4 and Thunderbolt 4 are powerful and convenient. Both use USB Type-C as a unified interface and only need one cable to perform multiple functions such as screen display, charging, and data transmission.
Both in appearance and function, USB4 and Thunderbolt 4 have many similarities. It is not so easy to tell the difference between them.
USB 4.0
In 2019, the USB 4.0 version was announced, and it no longer has many confusing names like the previous version. Its transmission speed can support 20Gbps, and the maximum transmission speed has reached 40Gbps. Most importantly, USB4 only uses USB Type- C interface and must support PD and up to 100W. In addition, USB4 is also backward compatible with USB 2.0 and USB 3.2 and supports Thunderbolt 3/4.
The Evolution of Thunderbolt
Thunderbolt is a high-speed I/O interface developed by Intel in 2009. Its main purpose is to be used as a transmission cable between computers and other devices, hoping to replace and unify a large number of various interfaces on computers. Intel released the first generation of Thunderbolt in 2011, the interface is integrated with Mini DisplayPort, the transmission speed can reach 10Gbps, and up to six peripheral devices can be connected through the Daisy chain.
Thunderbolt 2, which was launched in 2013, has doubled the transmission speed to 20Gbps, and the interface is the same as the first generation, still using Mini DisplayPort. In 2015, Thunderbolt 3 was launched, and the transmission speed doubled again to 40Gbps. In addition, Thunderbolt has also made a major change in this generation, not only the interface is changed to USB Type-C, the maximum power supply is 100W, and it supports dual 4K video output or single 5K video output. It is precisely because of this decision to be compatible with USB Type-C that Thunderbolt 3 is more popular than Thunderbolt and Thunderbolt 2.
As for Thunderbolt 4, which was launched in 2020, the interface still uses USB Type-C. Although the maximum transmission speed is still 40Gbps, the bandwidth of PCIe has been upgraded from 16Gbps of Thunderbolt 3 to 32Gbps of Thunderbolt 4. Compared with PCIe devices such as external graphics cards, the transmission speed and performance of Thunderbolt 4 have been significantly improved. The charging power is still maintained at 100W.
What is the difference between Thunderbolt 4 and USB 4?
Both USB4 and Thunderbolt 4 use the USB Type-C interface, the data transfer rate also supports 40Gbps, and both support video output and 100W power supply, so it is difficult to distinguish the two interfaces, so what is the difference between USB4 and Thunderbolt 4?
The most obvious difference between the two lies in the following points:
1.Supported Bandwidth
Both support up to 40Gbps, but USB4 has USB4 20Gbps and USB 40Gbps, so the minimum specification only needs 20Gbps, while Thunderbolt 4 has only one specification of 40Gbps.
2.Charging Power
Both support up to 100W, but the minimum standard for USB4 is 7.5W, while Thunderbolt 4 is at 15W.
3.Data Transfer Speed
As for data transmission, USB4 needs to support at least 10Gbps of USB 3.2, while Thunderbolt 4 not only supports 10Gbps of USB 3.2 but also can reach 32Gbps through PCIe.
4.Supported Monitor
USB4 only supports single display, and there is no minimum resolution requirement; in contrast, Thunderbolt 4 can support dual 4K 60Hz display or single 8K 60Hz display.
5.System wake from sleep
The Thunderbolt 4 interface also supports waking up from sleep, for example, when you want to wake up a computer with a mouse or keyboard, which will save users a lot of trouble.
In general, although the specifications of Thunderbolt 4 and USB4 are very similar, Thunderbolt 4 has higher minimum specification requirements than USB4 to ensure its basic functions, and Thunderbolt 4 is compatible with USB4. Conversely, USB4 is not necessarily compatible with Thunderbolt 4.