I am having the exact same issue. I have pinpointed mine down to it happening over and including a Render Distance of 13 Chunks. My system is more than capable of running Minecraft at this. The higher the Render Distance, the worse it is. At 13 is happens in the distance, with the chunks that are now being loaded. But when I set it considerably higher, it happens all over the screen, on every single chunk.
How it looks at different Render Distances for me.