Framerate issues

Before the hotfix, I was able to get a stable 60 in most team fights. I have a decent rig with a GTX 960.

Now, after the hotfix, my game keeps plummeting to 30 everywhere. I had no problems until after the hotfix. It’s made games near-unplayable, and it’s only gotten worse with time.

Is anyone else experiencing this? Would the hotfix mess with framerate somehow?