I'm trying to mine with Ubuntu 20.04 and a RX470, but I have some problems installing the AMD drivers.
I tried different versions, but I got always some errors when the installer compiles the kernel module.
The latest Ubuntu kernel 5.4.0-58 breaks compiling the amdgpu-pro kernel modules (except for amdgpu-pro-20.45-1188099-ubuntu-20.04 , but that isn't supported by most mining software).
I downgraded my kernel to 5.4.0-42-generic and was then able to install the amdgpu 20.20 drivers without issue.