Video issues

I loaded both new snapshots to check out the banners. However, I saw mostly white blocks all around me, with the blocks constantly flickering between white and the normal block. I thought it might be an issue with the resource pack I use so I unloaded but still got the same result. After that I checked various video settings in game with no result. Loading a brand new world I didn't have a problem, until i put something in my hot bar and switched to that item and the video started glitching again. It was fine when I looked at the ground but as soon as I looked up, it started again.