Thunderbolt 4 and USB 4.0 have rapidly become the connectivity standard for top-of-the-line laptops and computers, including high-performance gaming models. Each of these technologies features a USB Type-C (USB-C) connector capable of achieving speeds of up to 40Gbps, and supports video and power passthrough.
Given the many similarities between these technologies, it can be challenging to discern the differences between them. Indeed, there is a great deal of technical information to navigate. However, we have distilled this information as much as possible to provide clarity on the distinctions between these connection types. While it's difficult to make a wrong choice when purchasing devices with either Thunderbolt 4 or USB 4.0 ports, having a better understanding of their unique features will empower you to make an informed decision.
But before giving to know more about their differences, we need to have a basic knowledge of Thunderbolt 4 and USB 4.0.
Thunderbolt technology, also known as Thunderbolt cable, made its first appearance at Apple's WWDC 2011 event, alongside the launch of the first compatible device, Apple's MacBook Pro. Thunderbolt combined DisplayPort and PCI-Express technologies into one cable, enabling high-resolution displays and high-speed data transfers of up to 10Gbps.
Thunderbolt 2 doubled the bandwidth and added support for DisplayPort 1.2, while Thunderbolt 3 increased the bandwidth to 40Gbps.
The latest Thunderbolt technology, Thunderbolt 4, was unveiled by Intel® at CES 2020. This cutting-edge technology is capable of powering high-speed data transfers, device charging, and external video display. Thunderbolt 4 has a bi-directional bandwidth of up to 40Gbps, making it four times faster than USB 3.2 Gen 1. It is compatible with PCI-E, DisplayPort, and USB 4.0, and is also backward compatible with previous iterations of Thunderbolt via a USB-C connection. Thunderbolt 4 requires a minimum PCI-E data transfer rate of 32Gbps, which allows for superior performance and faster transfer rates.
Thunderbolt 4 also has impressive video capabilities, supporting up to two 4K60Hz monitors or a single 8K60Hz monitor.
Additionally, Thunderbolt 4 provides enhanced security features such as Direct Memory Access (DMA) protection. This technology creates virtual memory for every connected device, blocking access to system-wide memory and physically preventing DMA attacks.
USB, or Universal Serial Bus, has been the standard connection for peripherals to computers since its introduction in 1996. The latest version, USB 4.0, was released by the Implementers Forum on August 29, 2019. It is based on the Thunderbolt protocol and offers speeds of up to 40 Gbps. USB 4.0 is backward compatible with USB 3.2 and USB 2.0, although an adapter is required for the USB-C connector.
When compared to Thunderbolt 4, USB 4.0 does not support dual monitor displays. However, it can handle DisplayPort 2.0 with an impressive 8K or 16K resolution at 60Hz, and can transmit data at up to 80Gbps in one direction. It is also fast enough to connect an external GPU and can deliver up to 100W of power, which is similar to Thunderbolt 3.