I followed these instructions as well was not able to get it to work with my 5600xt on PopOS 20.10. After using ./amdgpu-install --no-dkms --opencl=rocm the command clinfo wasn’t even available. I had to install in separately and it showed 0 platforms even after restart.
EDIT 1
I also tried uninstall my drivers and installing the 20.40 drivers (per one of the posts) and got this error on executing sudo apt install amdgpu-dkms libdrm-amdgpu-amdgpu1
ERROR (dkms apport): kernel package linux-headers-5.8.0-7630-generic is not supp orted Error! Bad return status for module build on kernel: 5.8.0-7630-generic (amd64) Consult /var/lib/dkms/amdgpu/5.6.20.906300-1164792/build/make.log for more infor mation. dpkg: error processing package amdgpu-dkms (--configure): installed amdgpu-dkms package post-installation script subprocess returned erro r exit status 10 Errors were encountered while processing: amdgpu-dkms E: Sub-process /usr/bin/dpkg returned an error code (1)