Specs:
R5 3600 on 4.4GHz
16GB RAM
RX 6750XT on 2800MHz
Game on Samsung EVO SSD
I know this issue is decades old, but it seems like nowadays it's only an AMD-GPU related problem. However, I'm not sure since i think there are some RX 5000/6000/7000 series users (also other AMD cards) who don't have this problem. My old RX480 8GB also had this problem.
The problem only exists in DayZ; every other game is fine.
I'm playing on 1440p, running on Chernarus with mainly 140-190fps on extreme settings, 2000m Viewdistance, and 1300m object distance. GPU utilization hovers around 70%-90%. When I look at or am in certain areas, the GPU utilization goes down to around 30%, and I lose a lot of frames (big cities like Chernarus are heavy - down to 40fps GPU, 20% load).
I can literally stand on a hill and watch in one direction with smooth FPS and full GPU utilization. But when I turn around facing certain areas, I drop down to 20% GPU utilization. Even if I stand against a wall facing in a direction where a lot of structures or objects are, the GPU just throttles down.