During Apple's "One More Thing" Event this past week, Apple talked a lot about its new M1 processors and the first Macs to be released using them. The company went into detail about the specs of the processor, but they left more questions unanswered than they actually addressed. One of the things mentioned and completely glossed over was Thunderbolt 3. Many people were curious about what the difference is between Thunderbolt 3 and Thunderbolt 4 and their companion USB 3 and USB 4, including some in the media.
Thunderbolt 4 is less of a new specification and more of an updated certification. The underlying technology has not changed, and almost all USB 3 and USB 4, as well as Thunderbolt 3 and Thunderbolt 4, devices are interchangeable. The major difference in all of these names is USB 4's ability to turn all upward flowing channels into downward flowing channels. This allows for great video support on monitors but does require the disabling of other capabilities. This is to support DisplayPort 2.0, which requires double the bandwidth available to USB 4's upper version. In fact, USB 4 will not be marketed as such in documentation and packaging. Instead, it will be labeled by speed - USB 20Gbps and USB 40Gbps. To support DisplayPort 2.0 at 8K, you'll need to have the 40Gbps version.
Another positive for USB 4 will be the addition of power delivery, which will not be available on all USB 4 ports. However, the wattage has not increased, so you're still stuck with a proprietary charger for gaming laptops. For all of the changes and differences between USB 3 and USB 4, as well as Thunderbolt 3 and Thunderbolt 34, check out the guide on Tom's Hardware.
Scott is a developer who has worked on projects of varying sizes, including all of the PLUGHITZ Corporation properties. He is also known in the gaming world for his time supporting the rhythm game community, through DDRLover and hosting tournaments throughout the Tampa Bay Area. Currently, when he is not working on software projects or hosting F5 Live: Refreshing Technology, Scott can often be found returning to his high school days working with the Foundation for Inspiration and Recognition of Science and Technology (FIRST), mentoring teams and helping with ROBOTICON Tampa Bay. He has also helped found a student software learning group, the ASCII Warriors, currently housed at AMRoC Fab Lab.
Avram's been in love with PCs since he played original Castle Wolfenstein on an Apple II+. Before joining Tom's Hardware, for 10 years, he served as Online Editorial Director for sister sites Tom's Guide and Laptop Mag, where he programmed the CMS and many of the benchmarks. When he's not editing, writing or stumbling around trade show halls, you'll find him building Arduino robots with his son and watching every single superhero show on the CW.