I think I'm experiencing a CPU bottleneck, for example, a game called Smite which I play mainly I run at maximum at 75FPS (my monitor is an ultra wide and runs at 75Hz) and never even in the most demanding times drop any frames, however, when I try and play WoW, I really struggle with my FPS and find that I seem to stutter quite a lot, it doesn't seem to matter if I'm running at low graphics or high the issue persists.
My System is on my profile, but I will just state the processor and GPU:
i7-3770k (running at 4.2GHz)
AMD r9 Fury X