Unity Editor without the " -force-opengl" commandline is unusable

Not very long ago, this was not an issue. Something changed and I'm losing my mind over what.

I have a Nvidia GeForce 770 GTX as my primary GFX and an onboard Intel something something. I thought that for some reason, unity was using the Intel but I disabled it from BIOS and turned off it's interference in Multi-Monitors and forced the PCIx to go always.

Thing is, the performance in the viewport and the render window is not workable at all... especially, in run mode. Only by adding the -force-opengl parameters, I'm able to get back the exact behavior as original. So even disabling the built-in onboard GPU, I was not able to gain the lost performance. Which meant it is either running in some kind of safe mode or CPU 100% rendering.

I'm sad.

 

Ok, as per the manual here: http://docs.unity3d.com/Manual/CommandLineArguments.html

The -force-d3d9 option is the default on and is not required to explicitly mention. Turns out, after I mentioned it, everything was running smoothly again just like with -force-opengl. After a few experiments, I realized that by default, Unity runs in DX11 mode for me. And that is way too laggy.