Thunderbolt 3 and Thunderbolt 4 are both proprietary interface standards developed by Intel. They both use the same USB-C connector and offer high bandwidth for data, video and power.

The main differences between Thunderbolt 3 and Thunderbolt 4 in detail are:

Bandwidth

Bandwidth is the maximum data transfer rate that an interface supports. Thunderbolt 4 offers a constant bandwidth of 40 Gbps, while Thunderbolt 3 offers a bandwidth of up to 40 Gbps. This means that Thunderbolt 4 generally allows for faster data transfer rates than Thunderbolt 3.

The actual bandwidth available to a particular device or application may depend on how the bandwidth is divided. For example, a Thunderbolt 4 dock connecting two 4K monitors and an external drive may divide the bandwidth to meet the needs of all connected devices.

Minimum requirements

Thunderbolt 4 has higher minimum requirements than Thunderbolt 3, especially for supporting PCIe data. Thunderbolt 4 devices must support 32 Gbps PCIe bandwidth, while Thunderbolt 3 devices only need to support 16 Gbps PCIe bandwidth.

PCIe is a standard for connecting high-speed devices such as graphics cards, SSDs, and RAID arrays. Thunderbolt 4's higher PCIe bandwidth allows these devices to be connected and used faster.

New features of Thunderbolt 4

Thunderbolt 4 offers new features such as support for up to four Thunderbolt ports per device and the ability to connect two 4K monitors or one 8K monitor.

• Support for up to four Thunderbolt ports per device: Thunderbolt 4 devices can support up to four Thunderbolt ports, making Thunderbolt 4 a more versatile interface for connecting devices.

• Ability to connect two 4K monitors or one 8K monitor: Thunderbolt 4 devices can connect two 4K monitors or one 8K monitor. This makes Thunderbolt 4 an ideal interface for connecting desktop computers and high-end monitors.

Thunderbolt 4 also offers a number of additional features not included in version 3, such as:

• Wake on LAN: Thunderbolt 4 devices can connect to the network via Thunderbolt even when they are turned off.
• USB4 Compatibility: Thunderbolt 4 devices are compatible with USB4 devices.
• PowerDelivery 3.1: Thunderbolt 4 devices can deliver up to 100W of power.

Thunderbolt 4 is the current version (2023) of the Thunderbolt standard and offers a number of improvements over Thunderbolt 3. The higher minimum requirements and new features make Thunderbolt 4 a more reliable and versatile interface for connecting devices.

Here are some examples of using Thunderbolt 4:

• Connect a Thunderbolt 4 dock to your laptop to connect multiple external devices, such as a monitor, external drive, external graphics card, and charger.
• Connect a Thunderbolt 4 monitor to your laptop to use a high-resolution, high refresh rate monitor.
• Connect a Thunderbolt 4 adapter to your laptop to connect an older Thunderbolt or DisplayPort device.