To finish this topic:
I tested an 5700XT and now all works perfect.
PC2 is a very GPU intense game, but it doesnt seem to use much cpu time. Even my old I5 isnt stressed. When playing the fst. part of doom with the 5700XT, its the opposite, CPU alw. 99%.
But even the new card with 8GB VRAM delievers no perfect smooth gaming. (it shows over 60 Frames but its choppy often) Its smooth, then its not so smooth, maybe because i have only 8GB Ram. Or maybe my SSD is to old. Will test it on a new one.
Now i enjoy the game much much more. I started an iron man game on field marshal with protoypes trait (i like the additional tactical compoment that i have only a certain number of repairs for the prototypes and sometimes have to change the equipment during mission) and some negative ones (no overstrenght, bad logistics...) and now i am in stalingrad. I am looking forward for the real challenge, the maps i never played at all AND in iron man mode.
Btw.: I dont like generalissimus, not because of the difficulty. The wehrmacht just doesnt feel like the wehrmacht, more like the polish. I prefer fieldmarshal and if its too easy i use more bad traits.