Graphics settings for FPS

I have a lot of problems with fps. Game change graphic settings by itself sometimes and I endup with very laggy game. I am trying a lot of different things, online videos but I can’t get it to work. I manage sometimes to get 50 while I am standing but as soon I start to move it drops to 10 and it become very laggy.

I managed it few times to get on stable 30 fps and some players helped me setup settings but game keep messing with me so I forget what was the working settings.

I can play this game on beautiful graphics high resolution with constant 32 fps but I don’t know how to change settings to achive that.

I remember that in performance I had virtual texturing turned off and everything else on 50,
on graphics:
graphics quality 4
water quality 0
shadow lights 1
shader level 600
draw distance 2000
shadow cascades 2
shadow distance 250

effects: shun shafts
sharpen
anti alliacing

for other things I can’t remember if I had turned on or value…
I repeat I can have this game on beautiful with stable 32 without lagg but something change my settings from time to time and I have like unplayable 10 fps…

[editline]24th January 2016[/editline]

I figured out that parralax mapping has to be on 1