no VIRTUAL outputs on ":0"

Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192
eDP-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 345mm x 194mm
   1920x1080     60.02*+  59.93
   1680x1050     59.95    59.88
   1600x1024     60.17
   ... other video modes ...
   400x300       60.32    56.34
   320x240       60.05
DP-1 disconnected (normal left inverted right x axis y axis)
HDMI-1 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)
HDMI-2 disconnected (normal left inverted right x axis y axis)

Section "Device"
    Identifier "intelgpu0"
    Driver "intel"
    Option "VirtualHeads" "2"
EndSection

Section "ServerLayout"
    Identifier  "Layout0"
    Option      "AutoAddDevices" "true"
    Option      "AutoAddGPU" "false"
EndSection

Section "Device"
    Identifier  "DiscreteNvidia"
    Driver      "nvidia"
    VendorName  "NVIDIA Corporation"
    Option "ProbeAllGpus" "false"
    Option "NoLogo" "true"
    Option "AllowEmptyInitialConfiguration"
EndSection

Section "Screen"
    Identifier "Screen0"
    Device "DiscreteNVidia"
EndSection

GRUB_CMDLINE_LINUX_DEFAULT="quiet blacklist.nouveau=1 i915.modeset=1 gfxpayload=640x480 acpi_backlight=vendor acpi_osi=! acpi_osi="Windows 2009""

sudo apt-get build-dep xserver-xorg-core
apt-get source xorg-server

dpkg-buildpackage -rfakeroot -us -uc
cd ..
sudo dpkg -i xserver-xorg-core_n.nn.n-n_amd64.deb