Hello and thanks for your reply!
I only get a text-only boot menu. Headline is GNU GRUB version 2.04
The options are
Try Ubuntu without installing => black screen
Try Ubuntu without installing (safe graphics) => black screen (this is the modeset option, isnt it?)
Install Ubuntu
Install Ubuntu...
I would like to boot Ubuntu on my iMac Pro 2017 with Radeon Pro Vega 64. T2 Secure boot is deactivated. I tried it with Ubuntu 19.10 from an external usb ssd but I always get a black screen after the ubuntu boot menu. I guess it is a problem with missing drivers for the video card. If anyone...
Thank you, I just thought I post it under this thread because I have the same problem on a similar system. I edited my posting to make it more clear. Or is it still better to open a new thread? (I'm new here)
I have the same problem, also on an iMac Pro 2017 with Radeon Pro Vega 64. I tried to run Ubuntu 19.10 from an external usb ssd but I also got the black screen after the boot menu. If anyone has an idea it would be much appreciated.