Video errors with mac

[Popirey]

Hi,

I'm having a problem with the graphics. I've used virtual box to create a mac (yosemite), because mine is broken, and everything was ok. But now i'm having this problems, as you can see in the image (i've put the red rectangle).

My pc:
Windows 7 ultimate 64 bits
AMD Phenom(tm) II X4 955 Processor (3 CPUs), 3.2 GHz
8192MB RAM
DirectX 11

I've tryed changing 3D and 2D, but nothing happens...

Thanks for the help

[Perryg]

Mac OS as guest important information