Intel announced the Thunderbolt 4 specification with a series of improvements over Thunderbolt 3. The new standard will offer the same speed of up to 40 Gbps, but is designed to remove some of the confusion that has governed the Thunderbolt 3 realm for a decade.
Intel’s new Thunderbolt 4 connection isn’t technically faster than Thunderbolt 3, at least when it comes to overall throughput. But the company is justifying the new version number other ways: Namely, by cranking up the minimum requirements for systems with the new connection.
Thunderbolt 4 PCs will be able to connect to at least two 4K displays, whereas the previous requirement was just one. Additionally, the new connection supports PCIe data speeds up to 32 Gb/s, twice as fast as before. So you can expect to see incredibly fast Thunderbolt 4 external drives eventually. And you can be rest assured that at least one of your Thunderbolt 4 ports will support laptop charging, which is a bit of a hit-or-miss capability with current systems.
Thunderbolt 4 docks will support up to four ports in a smaller form factor, and Intel says host PCs will need to support waking from sleep when a device is connected to the dock. Furthermore, these systems will be required to support charging on at least one port, which should put the final nail in the coffin for barrel-type chargers in new laptops.
When you buy a Thunderbolt 4 cable, there’s only one flavor instead of the confusing mess of various USB standards that all use the same USB Type-C interface. There are three standard cable lengths of 0.2 m, 0.8 m, and 2 m that are supposed to be less expensive compared to Thunderbolt 3 equivalents. Come next year, we’ll also be able to buy Thunderbolt 4 cables that are 5 to 50 meters in length.
Intel says the new connection will also require protection against direct memory attacks (DMA) like the recent “Thunderspy” vulnerability. That attack could theoretically allow a hacker to steal data from your device, even if your PC was locked and had encrypted storage. Those DMA protections rely on Intel’s Virtualization Technology for Directed I/O (VT-d), which was supported on Thunderbolt 3 PCs, but was only strongly recommended for computer makers to follow. Now it’s an essential feature. VT-d creates an isolated memory region for devices, which prevents them from reading and writing to other locations.
It will also be interesting to see if Microsoft will eventually add Thunderbolt in its Surface products, being that security was the only deal-breaker. And with Apple moving its Mac lineup to ARM with no word on Thunderbolt support, it looks like Thunderbolt 4 could see a rather limited adoption.
Intel says it plans to ship Thunderbolt 4 controllers to manufacturers later this year, and you can expect to see it on Project Athena notebooks around the same time.