I followed this advice (mentioned above): https://www.reddit.com/r/Kubuntu/comments/1cdko49/comment/l1uf573/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button
It seems that "quiet splash" is the actual problem, not "nomodeset" (solution). I edited the GRUB entry as follows (with results added): 1) With only "quiet splash" (no "nomodeset"), default installation, fresh install of Kubuntu 24.04: only black screen, nothing happens. 2) Add "nomodeset" to "quiet splash": everything works perfectly. Also works permanently with editing of /etc/default/grub. 3) Delete "quiet splash" in GRUB and do not add "nomodeset" (or delete "nomodeset", if previously added): everything works perfectly (see Reddit link above). 4) Delete "nomodeset", after having added it to /etc/default/grub and updated grub previously, but leave the 'original' "quiet splash": computer hangs, completely unresponsive, after showing the following code: Booting a command list Loading Linux 6.8.0-31-generic ... Loading initial ramdisk ... 5) Again, boot without both "quiet splash" or "nomodeset": everything works perfectly. Also works permanently with /etc/default/grub. It went quite fast, but after "Loading initial ramdisk ..." I think the next code line was "enabling secure boot". It might be a problem with "secure boot" and "quiet splash". Secure boot is enabled in both my installations, so I can't try the other option ("secure boot" disabled in the EFI BIOS before installation). Workaround (for me): - Edit /etc/default/grub: the line "GRUB_CMDLINE_LINUX_DEFAULT=". Delete the words "quiet splash" (leave the quotation marks ''). - Run sudo update-grub -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2063983 Title: 24.04 Upgrade/Fresh Install results in black screen on reboot on AMDGPU system To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2063983/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs