[MC-59343] Nether fps drop

Everytime I go to the nether the fps drops to zero. If I try to move I get 1 or 2 fps but mainly it go to literally zero.

Environment

Windows 8.1 x64

this is most likely a computer issue and not an issue with the newest version

But on 1.7.10 I don't have that problem. Only on the beta version.

It happened with a World created with the 14w26b version. Now I create a new World with the 14w26c version and that doesn't happen.