it kind of shows wrong values for me.
e.g. i'm playing at 120fps, and it shows 136-146fps, even though the steam fps overlay says it's running at a steady 120fps (limited by the ingame limiter).
am i doing sth wrong?
You can use RTSS as an alternate source of FPS counter, this will be shown in HWiNFO as well.
But it's questionable who is right - 3rd party tools or internal GPU counters.
I also have exactly the same problem. Freesync 120Hz monitor with AMD 6700XT. Games are running at a solid 120fps and this is also reported at 120fps by Radeon software, however HWInfo64 framerate reading goes up and down anywhere from 100 to 140fps.
I've just done this too. Didn't really want to have another piece of software running, but at least getting the correct reading on my rainmeter widget now.