From a 4790K i don't know, i went from a 4.5Ghz 4690K to what you see in my signature and its anything from the same to just about twice the performance, any stuttering i did get on the 4690K is now gone.
Having said that the 4690K didn't have SMT, yours does.
Fair, amigo

Well, now we must decide what the safe quantity of logical processors is in order to avoid any chance of stuttering.
I'd recommend anything over 4-core/8-thread as the bare minimum for a gaming machine, without worries about lags and stutters.