I use my PC also for media, as it's connected to my TV by HDMI.

I have tried most KDE spins/distros, both on 5.2x and 6.x, and I noticed that on all other distros and Plasma versions, VLC uses between 8% - 12% cpu when I watch a 4K movie on my TV.
However on Solus it's only at about 3%. My PC is also noticeably cooler on touch while playing movies.
Note that it's only true for the KDE version, Budgie also sits at about 10% (Gnome + Cinnamon too on other distros) .

So I'm wondering what's the VLC "secret sauce" on Solus for KDE?

If there is no definitive answer I'd be curious to hear possible explanations for this from the devs.

    I don't know where I saw it but pretty sure the latest version of plasma passes much more of the graphics load handling over to the GPU (quite rightly) which could make quite a difference if your graphics card is a bit tasty.
    Other than that I would suggest Celtic Magic.

    rincor I assume your PC is using an Intel or an AMD GPU. When most distros updated the ffmpeg package past version 4.4 they had to drop VA-API support (GPU hardware acceleration) from VLC since VLC devs haven't managed to keep up with ffmpeg development. We on the other hand introduced a ffmpeg4.4 package which VLC builds against which allows it to keep VA-API compatibility. This means that on Intel and AMD GPUs VLC is able to use the GPU video decoders for most common video codecs (support depends on the GPU generation, newer ones support more codecs) while other distros have to use CPU decoding (uses more power and generates more heat). Arch Linux is another distro that uses a ffmpeg4.4 package just for VLC and so you would have had the same benefits there.

    I'm not sure why it wouldn't be working on Budgie. Perhaps it doesn't quite work in an X11 session but does in a Wayland one?

        ReillyBrogan
        That was exactly the kind of "low level" explanation I was looking for - I "knew" it couldn't be a coincidence and your explanation makes total sense. And yes, it is an Intel CPU (i7-1355U) fanless PC, so the temperature difference is easily noticeable when touching the passively cooled case.

        I'm used to VLC and it's always my first pick for videos (in part for the awesome VLsub feature) but are there any other media players that you know or would expect to correctly work with VA-API/HW acceleration, across all or most distros?

          MPV-based media players should work well. Celluloid (installed by default on GNOME and Budgie), Haruna (installed by default on Plasma), and smplayer are all in the repos and should have working hardware video acceleration.