Why TextureMemory 2d is so hight?

I have Gpu crash problem, i think its cause is texture streaming pool.
but it is wrong not correct.


‘Textture memory’ and ‘Render Target Memory 2d’ are causes!
This picture is captured in basic level(File>New Level>Basic)
Does anyone know what could be the reason for this problem and how I can free the gpu?

ps. How to Track What Causes a Higher texture memory 2d?