I wrote about slackware, because I know this system and used it before Hyperbola.
I am accustomed that when I do not use a laptop, it is cold and heats up during activity. And after switching to a hyperbola, the laptop is always warm. Which surprises me.
Configuration does not matter, the console itself is also warm.
Lenovo X200, X220, X230, T440P are all heating.
I conducted a small investigation and it looks like it is it despite closing the laptop cover, the processor continues to work.
Slackware Live: Idle system, screen off, but the system works = temperature 41 degrees.
Slackware Live: Idle system, screen enabled = 56 degrees
HyperBola: Various configurations, it is always around 57 degrees.
It seems that Libre Kernel cannot sleep the processor responsible for graphics.