I have a Dell Optiplex 7010 with an Intel i5-3570 CPU and 32GB RAM and has Kubuntu 22.04 installed on it. Recently I bought an RX 580 graphics card and installed it. It works fine except I can't get the hardware acceleration for video encoding to work. First I tried the AMD drivers, then the open source drivers. None of the video editing programs I have installed show the hardware acceleration being available. I tried transcoding a video with Handbrake. It used 95 to 98% of the CPU. I then installed the card and Handbrake in Windows. There I installed the AMD drivers and had no problem getting the hardware acceleration to work.
Does anyone have any idea what might have gone wrong?
Thanks.