Unity Lagging and Freezing

I just built a rig it runs Windows 8.1, I have 8 gigs RAM, AMD A10-7850 Kaveri processor, MSI A88X-G45 mobo, and a MSI N660 gc.

I have had success in running Unity, but it hits alot of spots where it lags and freezes in the Editor. The only way to prevent it from crashing and to have any semblince of working was to turn the Detail Resolution down to 512. I read online to use cmd to open Unity with -force-opengl and that seems the best i have tried -force-d3d11 and that dosnt seem as effective. Are there any suggestions that may help me to stop this lag issue and to help drop the number of Not Respondings?

i had some issues (crushes etc) when tried to use DirectX 11 and some specific shaders.

try to disable use of directx 11 from preference.