Intel details Thunderbolt 4, devices coming later this year

Intel today announced its new Thunderbolt 4 specification for improved peripheral connectivity.

While Thunderbolt 4 supports the same 40Gb/s maximum throughput as Thunderbolt 3, it slaps on an extra performance requirement. Passive Thunderbolt 3 cables cut performance in half when the cable reaches beyond 0.5m. Thunderbolt 4’s minimum requirement now mandates 40Gb/s performance for cables longer than 50cm. Cables under 0.8 are passive and function identically to Thunderbolt 3.

Data throughput technology has been increased as well. Because Tiger Lake will support PCIe 4.0, its throughput is doubled to 32Gb/s despite still only using 4 PCIe lanes. It now supports storage with up to 3,000MB/s speed. Video support has been expanded to drive two 4K displays or one 8K display.

Other quality improvements include support for docks with up to four Thunderbolt ports and PC wakeup through Thunderbolt dock connected keyboard or mouse.

This time around, Intel has also tacked on an additional certification requirement for Thunderbolt 4: DMA protection for Intel VT-d access. Intel VT-d is a virtualization technology that allows the virtual machine to directly communicate with the host system’s hardware, and direct memory access (DMA) protection prevents tampering when the virtual machine accesses the memory.

Intel will also be releasing the JHL8540 and JHL8340 standalone host controllers for computer makers, and the JHL8440 device controller for accessory makers.

Both Thunderbolt 4 PCs and peripherals are expected to arrive later this year.

Correction: The original article incorrectly attributed the bandwidth increase to the use of PCIe 4.0. Intel explained that Thunderbolt 4 is only making the increased speeds a minimum requirement. The Intel 8000 series Thunderbolt 4 controllers support 32 Gb/s data speeds over PCIe 3.0, as do some Thunderbolt 3 controllers available today.