One of the major advertised features of Thunderbolt 5 is something Intel calls “Bandwidth Boost”. Thunderbolt 5 is capable of up to 80Gbps bi-directional bandwidth, which already is double that of Thunderbolt 4. But Bandwidth Boost can increase this to up to 120Gbps in one direction for even greater display and data capabilities.

How it works

Thunderbolt 5 utilizes what is known as PAM-3 Technology in order to achieve these 80-120Gbps bandwidths. While the exact details of PAM-3 are not that important for the end user, those curious can find more details on the technology here. 

For Bandwidth Boost specifically, the 120Gbps is not generated out of thin air. Instead, the data transfer over Thunderbolt 5 operates in an asymmetric mode, where 120Gbps are allocated in one direction, and 40Gbps are allocated to the other direction, resulting in the same amount of overall bandwidth.

This extra 40Gbps can be dynamically allocated based on the demand. Where this especially comes into play is with displays. Bandwidth Boost over Thunderbolt 5 allows you to connect up to 2x 8K displays at 60Hz or 3x 4K displays at 144Hz. It can even handle up to 540Hz on a single 1080p display. Bandwidth Boost will only activate when needed, such as when you connect 2x 8K displays. That way, you don’t need to worry about losing out on any bandwidth in one direction if you don’t have to.

All this to say that the ability to connect large scale display setups with multiple 4K or 8K displays is now possible with Thunderbolt 5 and Bandwidth Boost!

While Thunderbolt 5 is not common in many hosts at the time of writing this, it is expected to be adopted more widely in the near future. One host that it is available on is the M4 MacBook Pro, which we have done testing with already.