Regarding HDMI version the spec which I gave a link to claims; True Resolution : 3840x2160 at 60Hz (DisplayPort) ,3840x2160 at 30Hz (HDMI)
Some while ago I was researching this issue and found a specification page on the ASUS website which showed two formats for declaring the frame rate, one extended only to the 1920 value while the other went to the full 4K. From this I deduced that perhaps windows uses one report format while linux uses the other. I cannot locate that page now, it may have been taken down. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/1890418 Title: i915 does not expose vendor-specific extended HDMI timings/modes Status in linux package in Ubuntu: Incomplete Status in xorg-server package in Ubuntu: Incomplete Bug description: I have a Toshiba radius 11 laptop which has a 4 k native screen. I have connected an Asus PB287Q 28" external monitor (https://www.asus.com/us/Commercial-Monitors/PB287Q/specifications/) over HDMI which displays the full 4K resolution when running under windows10 but will only reach a maximum resolution of 1920x1080 under ubuntu 20.04, same hardware just dual booting. Under Monitor Preferences this monitor is detected as an "Ancor Communications inc 28" and the monitor preferences provides a number of resolution steps up to 1920. If I issue "xrandr --addmode HDMI-1 3840x2160" this resolution is added to the monitor preferences pick list but attempting to apply it results in "the selected configuration for displays could not ..." message To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1890418/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
