Yes, this old chestnut.
Just installed Ubuntu 20.04.
Can get into grub fine (therefore I don't think it's an EFI problem), and if I choose the recovery option then the screen gets as far as
Loading initial ramdisk ...
_
For all other options the screen is just completely black (the backlight is on).
Kernel options nomodeset, quiet, splash, acpi=off make no difference and Ctrl-Alt-F2 doesn't do anything.
How can it be made to work? Very disappointed :'(
Update: Super Grub2 Disk
It prints error: unknown filesystem. nine times then Entering rescue mode ... then a prompt grub rescue >.
However, if I run the live CD from the Ubuntu installer then
$ lsblk -o value -s TYPE /dev/sda1
vfat
$ lsblk -o value -s TYPE /dev/sda2
ext4
so I dispute that these are unknown filesystems.
