i915 is for the Intel GPU, but that’s besides the point.
As a shot in the dark, try enabling full composition pipeline in the Nvidia drivers.
Run nvidia-settings as root:
sudo nvidia-settings
Go to X Server Display Configuration → click Advanced at the bottom of the page → check the box for Force Full Composition Pipeline
Click Apply
Now click Save to X Configuration File and save it under /etc/X11/mhwd.d/nvidia.conf
Quit and reboot.
Make sure Sync to VBlank, Allow Flipping, and Use Conformant Texture Clamping are all enabled under OpenGL Settings when you launch nvidia-settings as your normal user (without sudo).