I have been getting this Rendering glitch lately, idk what causes it but the only way to ´fix´ it is using a 1.7 client....
I've been getting this too, very annoying. Tried all the usual stuff; removing mods, reinstalling, updating graphics drivers but still haven't found a fix. So yeah, any help would be greatly appreciated.
Last time I had this was when I was using a different version of Optifine than I was supposed to be using.
Well I can say that I'm using the most current Optifine and resource pack and am not having any issues such as yours. The only issue I'm having is floating nether blocks everywhere in sky in my far render distance and I'm not sure why.
The floating blocks are to do with the regioning plugin the server has. Only way to temporarily fix it is to re-log.
Problem is Chunk Loading option was removed in 1.8, that was my first move Fill actually. Rolling back my video card drivers did work, but causes me major lag, now I am lag less but this happens and I have to restart my client.