https://www.theregister.co.uk/2017/11/30/hdmi_2_1_specification/

The HDMI forum has released the HDMI 2.1 spec, and promised it can deliver 48Gbps if you buy new cables that support the jump from HDMI 2.0s 18Gbps.

But while the organisation has probably delighted gamers and 8K video watchers with that headline number, they'll have to wait until deep into 2018 to get their hands on kit that employes the new spec.