Rust is unplayable for me, stutter/judder...

So rust ran fine up until about 6 months or so ago now my game has massive stutter/judder and I’ve been trying for months to fix this, the game is basically unplayable. I get really high FPS and capping FPS to 60 helps but I get massive stutter if I drop below 60, I’ve tried enabling VSYNC but for some reason this game won’t let me force it through ANY means I’ve tried. I know this is related to VSYNC and screen tear or else capping FPS wouldnt make it smoother, so my question is does anyone know how to or have successfully forced VSYNC in rust? or has anyone fixed this issue I’m having?

Heres some videos of the stutter:

Also for reference it kind of looks like this if I get over 100fps it runs a bit smoother anywhere below that it stutters:

What about your PC Specs?

**This is my new build: **

Intel 6600K @ 4.5ghz
R9 390 MSI 8G
Corsair Vengeance 8GB DDR4 2400
EVGA 650w Gold
256GB Samsung SSD
256GB WD Black Edition

This is my old build:

Intel 4690K @ 4.2ghz
Gskill Sniper 8GB DDR3 1866
Antec 550BP
ASROCK Z97X Killer
256GB Mushkin Chronos
1TB WD Blue Edition

Both of them had this issue