MichaIng responded to a similar question that I posted on the DietPi forum, you can read his response here https://dietpi.com/phpbb/viewtopic.php?f=11&t=7436 . We’re wondering whether there’s a driver that’s present on the RPi image but not on the RockPi4 image. I have had the 7 inch display working with the Ubuntu image provided by Radxa, for what it’s worth. Anybody have any ideas?