Graphics glitches and artifacts with Ryzen 5 3400G APU
Same problems can be observed with Ubuntu 20.04 LTS / Ryzen 3 3200G / Gigabyte B450M S2H / 16GB (2x8GB) DDR4 3200.
Workaround 1:
Disable IOMMU in BIOS.
Workaround 2:
Add iommu=pt to command line in /etc/default/grub following the steps below.
-
Run
sudo nano /etc/default/grub -
Make the
GRUB_CMDLINE_LINUX_DEFAULTline look like thisGRUB_CMDLINE_LINUX_DEFAULT="quiet splash iommu=pt" -
Update grub by
sudo update-grub -
Reboot with
sudo reboot
Is there a third workaround ?
The prompt is displayed ok (same picture on both screen) Then my display is sliced horizontally Each slice is shifted
I disabled IOMMU in the bios, changed the grub conf Activated dual screen in bios too.
HDMI monitor on HDMI (full hd) VGA monitor on HDMI>VGA on a DP>HDMI passive adapter (1650x ???) This is not a hardware issue or bios setting issue as I have dual screen working
Fresh ubuntu 20.04 install with kernel 5.4
Found a 3rd workaround with this video https://www.youtube.com/watch?v=WWg8q_f7nI4
I'm currently using Ubuntu 20.10
While support for these devices has been in the kernel for a while, I've found I've had missing firmware when I see an update-initramfs. I also saw some AMDGPU-specific commits to upstream linux-firmware a little while ago, and tried the latest available deb package for Hirsute - it fixed all of my weird issues with the system, including requiring software IOMMU
YMMV, but try the 1.191 deb package under https://launchpad.net/ubuntu/+source/linux-firmware
Edit: step by step instructions as requested!
- Navigate to https://launchpad.net/ubuntu/+source/linux-firmware
- Expand the 1.191 arrow, under The Hirsute Hippo branch
- Download linux-firmware_1.191_all.deb
- Install the new firmware
sudo apt install /path/to/linux-firmware_1.191_all.deb - Reboot
Edit2: For reference, I have two AMD systems this really helped with. One is a Dell Inspiron 5585 w/ AMD Ryzen 3500U, the other is one I built with an AMD Ryzen 3400G.