Hi folks. Just registered an account after lurking here for months because I wanted to share how I got rid of all my stuttering and "white-out (when screen turns light due to loss of position tracking)" issues.
This won't necessarily work for everyone especially those with dated hardware. I'm running a 4790k with a 780ti and could not stand how badly the game performed in the rift. Tried all the suggestions here to no avail but then remembered a trick I used way back to get battlefield 4 running smoothly.
What's the trick? Adjusting the system core parking settings. I'm not expert on this but it has to do with how the OS handles the availability of the cores. Long story short, the utility provided in the link below will allow you to set the cores to never be parked.
I tested this by turning it on and off and have confirmed that this will resolve the stuttering. I'm running at max settings with blur and AA turned ON and shadows on best quality and there is almost zero stutter except inside stations where it happens sporadically. Could not believe this old trick would make such a huge difference.
I have no idea what the long term consequences are by setting the cores at 100% availability so proceed at your own risk. I'm finally enjoying the hell out of E

and hope you guys get the most out of it also with this method.
Good luck!
Oh here's the link to the utility:
http://coderbag.com/programming-c/cpu-core-parking-manager