It's unfortunately a problem with the Unity engine so it depends on whether or not the developers even notice the issue, rather than it being a deliberate choice by the developers. I'm not hopeful, but at least we have the OpenGL workaround.
If you look up a few posts, you'll see that a workaround has already been found by forcing the game engine to use the OpenGL renderer. I just played for 2 hours like that and didn't run into any graphical errors or instability.
You can actually do that by manually changing the video settings in the registry if you're familiar with how to do that. I discovered this by accident trying to make fullscreen work. Change HKEY_CURRENT_USER\Software\Obsidian Entertainment\Pillars of Eternity\_currentDisplayMode_h1512211402 to 0.
Thank you it works! I just hope the OpenGL renderer is stable and isn't prone to any graphical glitches. I wonder if this trick works on Wasteland 2 as well...
Fullscreen doesn't work atm. It always runs in borderless windowed mode whether the fullscreen option is checked or not, though it seems to be locked to your desktop resolution.
Were you able to use fullscreen before? It hasn't worked for me at all. I'm also in the same boat of wanting to use G-Sync with the additional problem of poor performance/severe stuttering with windowed mode games.
I'm surprised this was not fixed during the beta but...fullscreen does not work. The only thing turning on the fullscreen option does is make the game minimize when you alt+tab. The game stays in borderless windowed mode and does not behave any differently from windowed mode otherwise. Unfortunately I tend to have performance problems with games running in windowed mode so I can't stop the game from stuttering, which I know it won't in fullscreen mode.
My system:
Windows 7 SP1 64 bit
Intel Core i5-4670k
16 GB RAM
GTX 970 driver v347.52