In Rock Pi S Linux images not booting people say that boards from before 2022 cannot boot kernel 5.x.
Whereas here jack from the radxa team suggests using an Armbian build with kernel 5.x: Rock PI S Allnet china -- 3 years old ! -- no kernel v5
I have tried Armbian_22.08.0-trunk_Rockpi-s_bullseye_current_5.15.58_minimal.img.xz, but to no avail: only the green LED stays lit.