Guys, I had the same thing happen to me, just recently too. Coincided with the Win 10 Creators update.
My framerate in Oculus Home was a constant 90fps, yet I saw juddering of the screen every few seconds, randomly. I reinstalled all Oculus software and moved my sensors around the room, installed a usb 3.0 card (inateck) and the judder still was there.
I installed Oculus Tray Tool, and turned on the Visual Hud Display, choosing Compositor Render Timing from the list. I saw that compositor frame drops were happening at the same time my headset twitched a frame.
Maybe a program in the background could be the cause? I found Afterburner (with Rivatuner osd), DisplayCal and Color Profile Keeper (to force icc profiles) were polling in the background. As soon as I exited all these programs, Judder has stopped. Just exiting one was not enough.
I think, that the Creators update has somehow messed with how Oculus Rift is prioritized. Turning game mode on / off makes no difference to the judder.
Please look into this Oculus.