Originally posted by Nightweaver20xx:

My system should be able to easily handle Valheim without heating up that much.

How so ? Polygons and textures are not what puts the most stress to the GPU these days (see UE5's Nanite polycount and then disable Lumen and notice how much performance you will get).
If you want to improve them GPU temps, improve its cooling system.
Or, as a workaround, limit your framerate.

Originally posted by AAND:

This problem needs to be solved by the devs and is probably related to the unity engine too.

I heard about this on Subnautica Community forum and I'm yet to hear what the problem actually is about, perhaps one cannot describe an imaginary issue

Originally posted by AAND:

Sometimes it seems that graphic cards run at maximum if you dont tell them not to do it by limiting it yourself.

They were designed to have specific power output, it is up to the user to use it (or not).