Black screen and then the game "freezes"

[Hearthfire]

So I've had this problem for a few days now and I've tried a lot of things, the problem is that the game freezes after a few minutes of being in game, and then unfreezes, however the screen still appears frozen, but I AM in game, I can move, shoot, everything, but the screen is frozen.
I have tried putting gmod into windowed mode, have tried setting -dxlevel 8 in the launch options, verifying the files, reinstalling gmod, reinstalling steam, REINSTALLING WINDOWS, but I still have that problem, I don't have any addons installed either.

I doubt it's my computer considering my specs:

R9 290x
AMD FX-8350
etc...

I can run most games maxed out without ever dropping below 60 fps except certain things [I]*cough* watch dogs *cough*[/I].
Any help is appreciated