Fps Drop ̶t̶h̶e̶ ̶b̶a̶s̶s̶

When i play in minecraft 1.9pre 4 after 5 min minutes of gameplay,I passe to 170 fps to 42 fps...

You can see my graphics card...In 1.8 I HAVE 600 FPS IN A VOID WORLD !!!

I have no ressource pack,i have nothing!

When i read that:
First the answer to the most asked question: We are currently planning to release the final version of Minecraft 1.9 next week, on Thursday, 25th of February 2016. (UPDATE: the release date was moved to Monday, 29th of February 2016)

I say,that gonna be impossible,
https://youtu.be/E0DHZ17iXTM?t=37s

YOU SHALL NOT RELEASE MINECRAFT 1.9 ON MONDAY!!!