When I built a PC with Athlon 200GE and installed Debian, the desktop environment did not start. I was able to research and move it, so I will write down how to do it.
CPU: AMD Athlon 200GE GPU: Raedon Vega 3 (with built-in CPU) Motherboard: ASUS PRIME B450M-A OS: Debian 10.3 Desktop environment: LXQt
--Prepare a USB memory to install Debian. -Radeon ™ Software for Linux® 19.50 Release Notes --AMD "Radeon ™ Software for Linux" ® Download the driver "amdgpu-pro-19.50-967956-ubuntu-18.04.tar.xz" from "version 19.50 for Ubuntu 18.04.3" and put it in your USB memory.
--First, install Debian normally. --When the installation is completed and restarted, the desktop environment does not start and the console screen with white characters is displayed on a black background. --If you don't see the console screen, you should see it with Ctrl + Alt + F2, etc. --Log in and insert the USB memory containing the driver. --Switch to superuser (sudo is fine) and mount to / mnt. --Copy the contents to your home directory. --Unzip "amdgpu-pro-19.50-967956-ubuntu-18.04.tar.xz".
username@debian:~$ tar -xf amdgpu-pro-19.50-967956-ubuntu-18.04.tar.xz
--Enter the generated directory and run the following command as superuser (sudo is OK) to install.
root@debian:/home/username# cd amdgpu-pro-19.50-967956-ubuntu-18.04 root@debian:/home/username/amdgpu-pro-19.50-967956-ubuntu-18.04# apt install ./amdgpu-core_19.50-967956_all.deb ./amdgpu-dkms_19.50-967956_all.deb
――It will take some time, but it will be completed once the installation is completed. Unmount / mnt and reboot.
The desktop environment can now be started by the above method. It took me a while to get to this solution, but once I knew it, it was a tedious and easy task.