Ah, thanks. It’s a red herring as it turns out: GRUB_TIMEOUT is set to 5 on this Thinkpad and also on a Dell XPS that I checked. The Dell was installed clean with F43 KDE and gets the standard GRUB boot menu, the Thinkpad will only work if I install F43 Workstation then install KDE over the top of it (using it right now). The Thinkpad has a 5s timeout in /boot/grub2/grub.cfg but it doesn’t go into the GRUB menu on boot at all. The Dell likewise has the standard 5s timeout in /boot/grub2/grub.cfg. The /etc/default/grub files on both machines are identical, and contain GRUB_TIMEOUT=5.
There are a bunch of other settings in /etc/boot/grub2/grub.cfg controlled by e.g. feature_timeout_style, menu_show_once, menu_auto_hide, menu_hide_ok and so on. GRUB is a dark art at the best of times, and these ain’t they!
I guess I’ll put the efibootmgr timeout back to 0. Interestingly, on previous installations (Debian IIRC) the value set through efibootmgr was non-zero, and I though I’d used that to change the amount of time that the GRUB menu was on screen, but I might have been fooled by a placebo effect.
you may have fallen foul of this issue
I was pointed at that before. I don’t believe it’s the same issue, mainly because not only do I get a black screen with a very small underscore cursor at the top and nothing else (it’s a 4K screen) but the machine actually crashes as indicated by the caps lock light not changing state when I hit the key multiple times. However, strangely enought for a hung machine, if I hit the power button Fedora comes to life to complete the shutdown. So perhaps it’s not crashed but in some strange dormant state that I’ve never seen before where it’s basically asleep or hibernating but responds to the power switch.
All I know is that as of now, and after installing more than half a dozen versions of Linux on at least 3 separate SSDs I have a working machine whereas when I do the standard KDE install - which has always worked previously - I get an unusable machine.
Another slight wrinkle: I added the rpmfusion drivers since the machine has an RTX 3500. I could run glmark2 e.g. on the RTX 3500 but after a while and after installing some other software I now get a seg fault when I try to run glmark2 on the Nvidia GPU. That’s also happened every time I’ve thought I had a working F43 installation. Arch did perform better. I have several machines running Fedora 43 and having Nvidia GPUs from a 3050 to a 5080 and - last time I checked! - they’re all running fine. It seems that there’s something specific about this machine that is not playing well with Fedora & KDE.