I just upgraded my computer from a R9 380 4gb to a RX 580 8gb
I have an FX 8350.
I could get like 200+ fps throughout the game with my R9.
Now i get like 140 dropping to 80 during the game.
In other games it works just fine, solid 60 fps on witcher (i use v-sync on that game) etc what can i do?