@steveurkel: The old standard speed HDMI cables can't do 4k60 but the high speed ones introduced for 1.4 ages ago should be fine. I wonder if they are confusing standard on connectors on TVs where if they support HDMI 1.4 they can do 4k but only up to 24fps. I'd be surprised if any 4k TV didn't support 2.0 though.
Also if I understood Jason right he seemed to think there was a 30fps cap at 4k on PS4 Pro. This isn't the case. Digital Foundry have a write-up of the first 4k60 game here: http://www.eurogamer.net/articles/digitalfoundry-2016-hands-on-with-mantis-burn-racing-on-ps4-pro
ComradePenguin's comments