Sorry for not helping you here but I have owned this game since launch day and have over 200 hours of MP and this game is a lost cause. I have done every tweaks possible to no avail. IW didn't even made something to optimize the game in their latest patch. Nothing!
They prefer adding things that no one ask for but close their eyes on the obvious. The game runs like ****. I'm just on the verge of uninstalling this POS.
Sorry again for the rant but I have had enough. I have 24 other big demanding games like Metro LL, Farc Cry 3 and all run well on Ultra but can't play this joke of a game on medium.