[xubuntu] 16.04 freeze

Hello,

I have a problem with my XUBUNTU, its freeze sometimes and i can't do nothing, expect press the power to restart it.
I use before i installed XUBUNTU Win 8.1, it worked without any problems and freeze.

Mostly if I watch streams or videos on Youtube it freeze, but sometimes if I don't use the browser it happened too (for example if I use XAMPP with DBeaver).

My Notebook:

Acer Aspire ES1-311-C82S
(More Infos about it: http://www.notebookinfo.de/produkte/...-007/00025475/)

(Im from Germany, sry for my english)