AMD Radeon Graphic Card Seen as 'Unknown Display' after Installing Ubuntu Bionic 18.04

Question

I am trying to install Bionic 18.04 on a Gigabyte Z390 motherboard. After 3 attempts I still get the same result over and over again when looking at Devices --> Displays --> Unknown Display.

We are speaking here of an [AMD] ASRock Radeon RX 5700 XT Taichi X 8G OC+ which is well recognized by Windows 7 on the same computer.

Hence the resolution gets stuck at 1024 x 768 ! what a feature on a 4K HD capable board.

Is there something broken within the hardware detection on Ubuntu Bionic 18.04 ?

Running the lspci command

$ lspci -nn | grep -E 'VGA|Display'

Returns

03:00.0 VGA Compatible Controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Device [1002:731f] (rev c1)

Which is quite laconic as a precise identification ... Maybe not a surprise there isn't any kind of driver installed.

Though this reference identify correctly the card as

1002:731F --- Navi 10 [Radeon RX 5700 / 5700 XT]

is reported on this webpage.

I am using 18.04.3 amd64 ISO image since the 18.04.4 image couldn't get the appropriate bcmwl-kernel-source package working with the installed kernel ...

I have seen some answers here like 'How to install AMD graphic drivers on Ubuntu 18.04' but I quickly run in not install-able packages due to missing / broken dependencies.

Why do we have to deal with such a mess when using Apple compatible hardware ?

In the About screen I see

Graphics llvmpipe (LLVM 8.0, 256 bits)
GNOME 3.28.2

llvmpipe isn't at all from AMD I believe. Why do I get this as Graphics ?

Answer 1

Well, I don't know why but on the 4th attempt and after installing the updates (like on the previous attempts), Ubuntu manages after the reboot to show a 4K HD display ... Without having to try to install or re-install anything.

The About screen saying:

Graphics AMD® Radeon RX 5700 XT

A further note : Installing the 18.04.3 ISO Image without access to the Internet installed Kernel 5.0 and the working MacIntosh Wi-Fi support from package bcmwl-kernel-source. Later the update installed Kernel 5.4 and the Wi-Fi Internet was still working on both Kernels.

When I tried installing 18.04.4 ISO Image it installed Kernel 5.4 and the Wi-Fi was not working. Trying to install bcmwl-kernel-source failed as well.