I am running RHEL 7.3.
The Xorg looks clean. Option “Overlay” “True” is what I am using in the config. Composite and Xinerama are disabled. The only complaint I see is ACPI failed to connect to the event Daemon.
RandR is showing disabled (also I believe its version 1.4)
Shared Memory Pixmaps are disabled
There is also a message indicating NVIDIA(0): Enabling 16bit RGB Overlays.
libglxserver_nvidia loaded as well as libglx (mesa I think)