render distance problem

You know the moment when your render distance is too high and there are fast moving images of the world flashing on your screen? I do, but do you know the moment when your render distance is at the minimum of 2 and your pc is still freaking out? I have this problem every time I create a new world but there is no problem when I create one in version 1.8. I want to play 1.9 properly so please fix this.