Why is my screen choppy when I play HD видео?

I am using Xubuntu 14.04 on an ASUS X55V (i3 CPU and Nvidia 610m GPU). I installed the recommended proprietary driven in the GUI (352.63). I installed Nvidia Settings, too, and it lets choose if I want to использовал the integrated gpu or the Nvidia GPU. When I am playing в видео on Youtube or in VLC I хан see it используй my GPU (but эксперт the picture шоу, it does not использовал видео engine... does it have anything to do with it?).
nvidia settings screenshot
I also ticked the ani-aliasing checkboxes, which include the following settings:

• Enable FXAA (ticked)
• Antiostrolpic filtering (override app settings-ticked)
• Texture quality (texture sharpening-ticked)

I installed the дополнительные Ubuntu restricted, well.
And lastly, I found this:
http://blog.riswan.com/2012/05/how-to-fix-slow-choppy-video-playback.html
I followed all the instructions, with не luck.

formatc2013@formatc2013-X55VD:~$ lspci|grep VGA
[00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)
01:00.0 VGA compatible controller: NVIDIA Corporation GF119M \[GeForce 610M\] (rev a1)][1]

I would like to know, what is the reason of this screen tearing, and what commands to run in order to fix it! Many thanks