Can't select anything more than 30hz when resolution set to 3840x2160

  • Hi,

    I am trying to set the refresh rate in the libreelec settings to 60hz while the resolution is set to 3840x2160, however for some reason the max refresh rate I can select is 30hz. I have been trying to debug this for the best part of a couple of days, so I am turning to the community for help!

    The TV I have is the Samsung 65" RU7100 which supports 4K at 60hz, and the cable I am using also supports 4k and is a micro HDMI to HDMI (this is the second cable I've tried and no luck with either).

    I am, using the HDMI 0 port on the PI (port nearest to the power connector) and I've added hdmi_enable_4kp60=1 in config.txt.

    What's wired is when I tested this on one of my monitors (the Dell U2718Q) which also supports 4k I could select 60hz, so I think the problem is specific to my TV. But I have also looked in the TV setting for an option like "Deep Colour" (I read that sometimes you have to change a TV setting to enable 60hz), but I can't find any relevant setting. The only option I found was HDMI "Input Signal Plus", but I think that is used for UHD and didn't have any effect.


    These are the cables I've tried and both work with the 4k monitor (I can choose 3840x2160 and 60 Hz refresh rate), just not the TV.

    Cable 1: KabelDirekt 1.5m Micro HDMI to HDMI Cable compatible: Amazon.co.uk: Electronics

    Cable 2: UGREEN HDMI D HDMI A , Cable, HDMI Type D , HDMI Type: Amazon.co.uk: Electronics

    Running tvservice -m CEA returns:

    Any help or advice would be greatly appriciated!

  • Taking things in a different direction, why do you need 4K60?

    I ask because so far the only media I've seen in that format is test media, not real media, and the GUI will perform (and look) better at 1080p than 4K because processing a 1080p GUI takes less effort and the TV will do a better job of upscaling Kodi 1080p output than Kodi will do upscaling a 720p or 1080p skin to 4K. Since real 4K media is 99.99% in [email protected], there's no need for the config.txt enable 4K60 (better for Pi thermals and power).

    Doesn't explain why you can't achieve 4K60, but if you don't need to.. ?