Dual boot ubuntu 18.04, GPU issues

Currently I am having to log into fresh install of Ubuntu with 'nomodeset' otherwise it black screens or the monitor loses signal. I have tried to follow this: "" as well as installing the AMD drivers from their website and both have the same effect.

I am using two monitors, one is hdmi (monitor) to display port (GPU) and the other HDMI. Both plugged into the GPU not the motherboard.

GPU: r9 390

CPU: i5-4690k

When I boot without 'nodemodeset' it picks up both monitors and at the correct resolution, but black screens after login. Any help would be appreciated, thanks.

*Secondly in my graphics config when Ubuntu actually booted with my r9 390 it said the driver = radeon, but if I'm using ppa:oibaf should this not = amdgpu? How do I force it to use the amdgpu drivers?

----------------------------------------------------------Final Edit------------------------------------------------------------

It seems I have managed to fix my issue, see my answer below

3 Answers

I think I have fixed my issue, I believe the issue was that it would use either radeon's driver which was unstable (black screen) or fallback to llvmpipe drivers, in short I had to blacklist radeon and force amdgpu drivers.

I have managed to reboot 4 times without nomodeset with no issue occurring. I can now also customise my resolution/refresh rate, and both monitors are supported and functional. In the case of someone else finding this post through a search engine here are the steps I took that worked for me on my r9 390.

• Install this PPA for the latest drivers - ""

then

sudo apt update && sudo apt -y upgrade

• Add this to /etc/x11/xorg.conf or /etc/xorg.conf -

Section "Device"

 Identifier "AMDGPU" Driver "amdgpu" Option "AccelMethod" "glamor" Option "DRI" "3"

EndSection

I did 1&2 following this - ""

• Add this to /etc/modprobe.d/blacklist.conf -

blacklist radeon

then

sudo update-initramfs -u

• Add this to /etc/default/grub -

GRUB_GFXMODE=1920x1080x32

radeon.cik_support=0 radeon.si_support=0 amdgpu.si_support=1 amdgpu.cik_support=1 amdgpu.dc=1 amdgpu.dpm=1

then

sudo update-grub

Found step 4 from here -

"How to set Display Resolution while having to use "NOMODESET" on boot"

&

""

This is what worked for me at the time of this post running Ubuntu 18.04. Black listing radeon may cause some issues if you do not have a driver installed, in my case black listing it caused Ubuntu to fall back to the llvmpipe drivers, so I had to add some lines to the grub file to use amdgpu as it was not automatically being used.

well, this is the problem with AMD cards you dont have to again and again and nomodeset just edit the grub file add the nomodeset , save and "sudo update-grub".

This was also the problem with Nvidia cards back in ubuntu 16.04 but now it runs without nomodeset. On linux mint it adds nomodeset on installing drivers.

I see you have the same GPU and CPU as I have. If you have any further problems, I would strongly advise you to add radeon.dpm=0 in your GPU options which disables the dynamic power management of the GPU. This solved black screen crashes for me.