Rendering issues after hardware upgrade

Question

I upgraded my PC from i3 6100 to Ryzen3 3200g. Only on Ubuntu, these issue happen, not in Windows 10. On Firefox, Chromium, wine windows, Clion and other programs.

These issues appear on screenshots too:

Answer 1

As explained here the issues are because of the IOMMU, do:

I found a solution here (panariga's "Workaround 2") with which I could keep the IOMMU enabled in the BIOS and without needing any custom drivers. I get a steady 60 fps running glxgears.

Workaround 2:

Add iommu=pt to kernel command line in /etc/default/grub:

sudo nano /etc/default/grub

Edit the line beginging GRUB_CMDLINE_LINUX_DEFAULT to look like this

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash iommu=pt"

Update GRUB:

sudo update-grub

Reboot

reboot