Issues with Linux + HD7850

So i have huge Issues with my Setup and Linux.

Everything is virtualized except i say otherwise.

I could install Kubuntu via VNC but then when i switched to my Graphicscard i didnt see anything.

Then Back to Debian Jessie (What i wanted to use anyway):

Freshly installed and then i want to add firmware-linux-nonfree to get the drivers working for my HD7850. Nope. When i want to start the System i am getting dropped to Terminal and i saw that XOrg freezed up. No Errors, no Warnings.

When i tried to install the proprietary Drivers (from Repository or AMD Site) i wouldn't even get to the Terminal. I had to enable VNC again to rescue it.

Back to the issue with firmware-linux-nonfree:

I upgraded to Kernel 4.2 to see if it solved the Issue: No luck.

Got myself a Debian Live iso with that package. Both, normal boot and boot in failsafe mode, freezed up (Not on the same Spot tho)

Then i tried to Boot it of without Virtualization: Normal mode freezes somewhere but with Failsafe mode i am finally getting through. So there must be something different to the virtualized one (And this is the main reason why i am posting it here)

What can i try to finally switch to Linux from Windows

Thanks in Advance