After playing around 10-15 minutes of DayZ, the textures suddenly become more "simpler" and the FPS drops to around 3-7 FPS.
- Legacy ID
I have the same issue. I found a way to temporary fix this problem : When it happens, Go to your "video settings" and change for example, the "Anti-aliasing" value.
I'm pretty sure this is a "Very" common bug/issue. Everyone I know is experiencing the same thing, on super high-end and old low-end PC's, and no amount of tweaking settings fixes the issue.
It's not a hardware issue like running out of VRAM or stressing CPU/GPU too much, personally, DayZ is only using around 30-40% on my CPU, and 35-45% on my GPU's.
this is a widespread issue which I have decided to use #0017013 for.
Please refer to that ticket for further information.