Short lags in game while moving in Ground RB, flying a plane or having intense fire fights?

I recently experienced lags in the game, it started with mikro lags just before the “Call of the Dragon” event started and was at this point unpleasant but still playable.
However after another update of War Thunder the lags got a big issue, to a point, where I was unable to play the game normally, changing settings to very low was not making it any better and trying to change game priority in the task manager to give it additional ressources did not work (access denied by system).
So, what did help to fix the problem?
A friend of mine told me about a Windows update I missed, I installed it and the big lag spikes were gone, leaving me again with the mikro lags.
I was able to get rid of those too after a long trial and error test phase, again experimenting with the graphic settings ingame.
Turned out, the FPS were capped at 75 FPS by Nvidia system system control, I removed the limit so War Thunder ran on the maximum of available FPS, letting me play without lags on relatively high graphic settings again.

I hope this experience report might be useful to other people with similar problems.