A config file for PRIME if NVIDIA KMS is enabled

Hello! I have Gentoo: Linux 3.16, X-Server 1.18.4 and Xrandr 1.5.

I’m using PRIME with a config:

Section "Module"
    Load "modesetting"
EndSection

Section "Device"
    Identifier "nvidia"
    Driver "nvidia"
    BusID "1:0:0"
    Option "AllowEmptyInitialConfiguration"
EndSection

I want try KMS on NVIDIA because I want to try GLvnd. I have been add “options nvidia-drm modeset=1” in /etc/modprobe.d/nvidia.conf and reboot. Then I have switched Driver “nvidia” to Driver “modesetting” in xorg.conf. X-Server can’t start. Does anybody have a working config file?

See:
https://devtalk.nvidia.com/default/topic/957814/linux/prime-and-prime-synchronization/post/4964506/#4964506
You can leave out the IgnoreABI, that was for the beta.