In a nutshell: Nearly a year after first introducing DisplayPort 2.0 with Alt Mode (remapping pins for USB-C), VESA has updated the tech for use with USB4. Although it does not expect devices to start implementing until 2021, the new spec ensures USB4 connections will benefit from the increased performance that DisplayPort 2.0 offers.
The Video Electronics Standards Association (VESA) introduced an upgraded DisplayPort 2.0 spec last year with an alternative mode for USB-C. At 77.4 Gbps, the tech has nearly triple the bandwidth of DisplayPort 1.4a.
On Wednesday, VESA released DisplayPort Alt Mode 2.0, which will bring DP Alt Mode performance to USB4 devices when they start rolling out. Ports with USB4 will have Alt Mode support for resolutions of up to 16K, higher refresh rates for 4K and 8K monitors, and improved performance for AR, and VR displays, and multi-monitor setups. Just as an example, the spec should be capable of running three 4K displays at 144Hz with 30bpp 4:4:4 HDR (with Display Screen Compression).
"VESA's updated DisplayPort Alt Mode spec includes a number of under-the-hood developments—including updates to interface discovery and configuration as well as power management—to ensure seamless integration with the USB4 specification," VESA board member Craig Wiley said in a press release.
Alt Mode will offer USB-C devices up to 80Gbps of link bandwidth. It will, of course, work through native DisplayPort legacy connections, Thunderbolt, and the upcoming USB4. While new USB-C devices using DP Alt Mode should start showing up later this year, Vesa says that it does not expect to begin seeing DisplayPort Alt Mode 2.0 implementation for USB4 until sometime next year.
While DisplayPort 2.0 won't be too widely used for 16K displays for a while, the extra bandwidth should be welcome for those running multiple 4K and 8K setups, which are becoming more common as monitor prices continue to go down.