Need help about resolution and something about FPS

[L.Z.]

hi everybody!

when i start to play rust i have 100 fps after 30 minutes after roaming my fps goes to 85 and never return to 100 i have set something wrong? i need to type something in console to restore the game's fps?

about resolution, i was trying to use a custom resolution but i think i have better fps on 1920x1080 why if i downgrade my res my fps don t grows? or the game is smoother? (i have a gtx1050).

I hope someone can help me! bye !