Hey I was having the same problem with the same processor, kernel 5.12 fixed the problem for me. If that doesn’t work you can try adding amdgpu.noretry=0 to your grub file (etc/default/grub at the end of the line: GRUB_CMDLINE_LINUX_DEFAULT=" default text amdgpu.noretry=0" then in console: sudo update-grub and restart). It happened to me in kde too btw so I’m not sure if gnome is the problem.