DisplayLink Forum - View Single Post - Ubuntu 20.04 Display Link with Ryzen (integrated graphics) SLOW refresh rate

raz · 08-09-2021, 09:14 AM

I've spent some 10h last week trying to get this to work and I feels somewhat like a beaten dog.

I find it really the lack of support and lack of interest in addressing this issue from DisplayLink side quite frustrating. I bought a AMD Ryzen 7 4800H Laptop with the specific purpose of using it with DisplayLink which turned out to be a big mistake.

Anyway, googling and trying a lot of different setups i finally got it to work some what decadently. To get it to work the quest was to find a combination of the proprietary AMD kernel modules, with a DisplayLink kernel modules, with a specific kernel at version of Ubuntu to work.

Reading a lot of threads online, it seems like "well, it works on my computer" is prevalent. Anyway, this is how i solved it (which might be outdated tomorrow if, the history Ubuntu and AMD compatibility issues during the last year(s) is any indication of the future)

Code:

1. Install Ubuntu 20.04.2
2. It comes with two kernels
    linux-image-5.11.0-25-generic (default)
    linux-image-5.8.0-43-generi

While the AMD and Displaylink kernelmodules both work in 
linux-image-5.11.0-25-generic. They do, however, not work together and once a
displaylink device is connected everything freezes until it is unplugged.

So downgade the kernal to 5.8.0-43, in my case
- in /etc/default/grub change GRUB_DEFAULT=0 to GRUB_DEFAULT="1>2" 
  (meaning select entry 1, then entry 2 in the grub boot menu, which should be 
   the next latest kernel)
- sudo update-grub
- reboot
- uname -r # to make sure you are using the 5.8.0-43 kernel

Install latest amd drivers in pro mode
- https://www.amd.com/en/support/kb/release-notes/rn-amdgpu-unified-linux-21-30
- amdgpu-pro-21.30-1290604-ubuntu-20.04 
- ./amdgpu-install --pro --opencl=legacy,rocr

Install latest displaylink dirvers
- ./displaylink-driver-5.4.0-55.153.run

Reboot.

Some considerations.

For me, the steps above makes things work a lot better with displaylink, and i can run two external monitors with acceptable lag (it is not perfect)

Issues:

I am unable to start the computer with the DisplayLink dock connected, It never reaches gdm.

Monitors over displaylink is still laggy at times

The AMD driver does not seem to play nice with x server. Gnome becomes unusable, due to window tearing. (I think there might be a xorg conf fix for it, but i have not dug into it). Using wayland does however seem to work out of the box. I am using i3 with X, which seems to work for the most part. Some programs, such as gnome-terminal, is still unusable.

Anyway, hope this helps someone.

08-09-2021, 09:14 AM	#10
raz Junior Member Join Date: Aug 2021 Posts: 1	I've spent some 10h last week trying to get this to work and I feels somewhat like a beaten dog. I find it really the lack of support and lack of interest in addressing this issue from DisplayLink side quite frustrating. I bought a AMD Ryzen 7 4800H Laptop with the specific purpose of using it with DisplayLink which turned out to be a big mistake. Anyway, googling and trying a lot of different setups i finally got it to work some what decadently. To get it to work the quest was to find a combination of the proprietary AMD kernel modules, with a DisplayLink kernel modules, with a specific kernel at version of Ubuntu to work. Reading a lot of threads online, it seems like "well, it works on my computer" is prevalent. Anyway, this is how i solved it (which might be outdated tomorrow if, the history Ubuntu and AMD compatibility issues during the last year(s) is any indication of the future) Code: 1. Install Ubuntu 20.04.2 2. It comes with two kernels linux-image-5.11.0-25-generic (default) linux-image-5.8.0-43-generi While the AMD and Displaylink kernelmodules both work in linux-image-5.11.0-25-generic. They do, however, not work together and once a displaylink device is connected everything freezes until it is unplugged. So downgade the kernal to 5.8.0-43, in my case - in /etc/default/grub change GRUB_DEFAULT=0 to GRUB_DEFAULT="1>2" (meaning select entry 1, then entry 2 in the grub boot menu, which should be the next latest kernel) - sudo update-grub - reboot - uname -r # to make sure you are using the 5.8.0-43 kernel Install latest amd drivers in pro mode - https://www.amd.com/en/support/kb/release-notes/rn-amdgpu-unified-linux-21-30 - amdgpu-pro-21.30-1290604-ubuntu-20.04 - ./amdgpu-install --pro --opencl=legacy,rocr Install latest displaylink dirvers - ./displaylink-driver-5.4.0-55.153.run Reboot. Some considerations. For me, the steps above makes things work a lot better with displaylink, and i can run two external monitors with acceptable lag (it is not perfect) Issues: I am unable to start the computer with the DisplayLink dock connected, It never reaches gdm. Monitors over displaylink is still laggy at times The AMD driver does not seem to play nice with x server. Gnome becomes unusable, due to window tearing. (I think there might be a xorg conf fix for it, but i have not dug into it). Using wayland does however seem to work out of the box. I am using i3 with X, which seems to work for the most part. Some programs, such as gnome-terminal, is still unusable. Anyway, hope this helps someone.