VR rivals come together to develop a single-cable spec for VR headsets

The spec uses USB Type-C cables to deliver power and DisplayPort video simultaneously.

Ars Staff – Jul 18, 2018 12:07 pm | 117

Credit: Andrew Cunningham

Future generations of virtual reality headsets for PCs could use a single USB Type-C cable for both power and data. That’s thanks to a new standardized spec from the VirtualLink Consortium, a group made up of GPU vendors AMD and Nvidia and virtual reality rivals Valve, Microsoft, and Facebook-owned Oculus.

The spec uses the USB Type-C connector’s “Alternate Mode” capability to implement different data protocols—such as Thunderbolt 3 data or DisplayPort and HDMI video—over the increasingly common cables, combined with Type-C’s support for power delivery. The new headset spec combines four lanes of HBR3 (“high bitrate 3”) DisplayPort video (for a total of 32.4 gigabits per second of video data), along with a USB 3.1 generation 2 (10 gigabit per second) data channel for sensors and on-headset cameras, along with 27W of electrical power.

That much video data is sufficient for two 3840×2160 streams at 60 frames per second, or even higher frame rates if Display Stream Compression is also used. Drop the resolution to 2560×1440, and two uncompressed 120 frame per second streams would be possible.

The new spec will ensure consistent and convenient connections for future VR headsets. Current headsets tend to use multiple cables, transmitting USB data separately from display data, which travels over DisplayPort or HDMI. The use of the thin Type-C connector will also be helpful for slim laptops and mobile phones, which generally lack full-size HDMI or DisplayPort connectors.

The specification also marks a point of agreement between companies that have often been rivals in the VR space. Oculus, Microsoft, and Valve all have their own VR platforms; while Microsoft and Valve have worked to provide compatibility between Windows Mixed Reality and SteamVR, respectively, Oculus has had a more strained relationship when it comes to software interoperability.

Consumer-level VR is still a nascent technology with an uncertain future ahead of it. This kind of consolidation and cooperation surrounding cables makes investing in VR a much less risky proposition for consumers, who can be assured that any VirtualLink-compatible system will work with any VirtualLink-compatible headset, regardless of which software platform it uses. It would be better still if it were matched by greater software-level cooperation, such that any VR program would reliably work on any VR headset to avoid fragmenting this still small market, but that may prove a bridge too far for these competitors.