#/etc/X11/xorg.conf.d/50-device.conf
Section "Device"
    Identifier	"Default Device"
EndSection

#/etc/X11/xorg.conf.d/50-monitor.conf
Section "Monitor"
    Identifier	"Default Monitor"
    HorizSync	30-120		# adjust to match your display's spec if known
    VertRefresh	56-61		# adjust to match your display's spec if known
    Option	"DefaultModes"	"on"
    DisplaySize	338 253		# 120 DPI @ 1600x1200 (optional: forces DPI to preferred value)
    Option	"PreferredMode"	#"1600x1200" (optional: used to achieve less than maximum native resolution)
EndSection

#/etc/X11/xorg.conf.d/50-screen.conf
Section "Screen"
    Identifier	"Default Screen"
    Device	"Default Device"
    Monitor	"Default Monitor"
EndSection