Not necessarily. Your CPU should be fine with the 1080 Ti. The only place where it would be noticeable would be in VERY CPU intensive games.
so if i had to change my processor what should i change it with my motherboard is socket 1150 LGA - Asus B85M-G
If you wanted to go large like your GPU I would recommend a i7-4790. If you want to overclock like your GPU then you could get the K version. If you aren't looking to go that big then I would recommend an i5-4690. But really, your CPU should be fine.
Not necessarily. Your CPU should be fine with the 1080 Ti. The only place where it would be noticeable would be in VERY CPU intensive games.
so if i had to change my processor what should i change it with my motherboard is socket 1150 LGA - Asus B85M-G
If you wanted to go large like your GPU I would recommend a i7-4790. If you want to overclock like your GPU then you could get the K version. If you aren't looking to go that big then I would recommend an i5-4690. But really, your CPU should be fine.
That CPU is going to hugely bottleneck a 1080 Ti. I wouldn't pair a locked i5 with anything more powerful than a GTX 1060. You're even going to take a hit with a 1070.