$ cat Xorg.6.log
[477079.273]
X.Org X Server 1.18.3
Release Date: 2016-04-04
[477079.273] X Protocol Version 11, Revision 0
[477079.273] Build Operating System: Linux 4.2.5-1-ARCH x86_64
[477079.273] Current Operating System: Linux triad 4.4.5-1-ARCH #1 SMP PREEMPT Thu Mar 10 07:38:19 CET 2016 x86_64
[477079.273] Kernel command line: BOOT_IMAGE=/vmlinuz-linux root=UUID=68e36202-4a60-4600-8241-09654d755001 rw
[477079.273] Build Date: 05 April 2016  05:24:02PM
[477079.273]
[477079.273] Current version of pixman: 0.34.0
[477079.273]    Before reporting problems, check http://wiki.x.org
        to make sure that you have the latest version.
[477079.273] Markers: (--) probed, (**) from config file, (==) default setting,
        (++) from command line, (!!) notice, (II) informational,
        (WW) warning, (EE) error, (NI) not implemented, (??) unknown.
[477079.273] (==) Log file: "/var/log/Xorg.6.log", Time: Sun Apr 10 12:14:38 2016
[477079.277] (==) Using config directory: "/etc/X11/xorg.conf.d"
[477079.277] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[477079.277] (==) No Layout section.  Using the first Screen section.
[477079.277] (==) No screen section available. Using defaults.
[477079.277] (**) |-->Screen "Default Screen Section" (0)
[477079.277] (**) |   |-->Monitor "<default monitor>"
[477079.277] (==) No monitor specified for screen "Default Screen Section".
        Using a default monitor configuration.
[477079.277] (==) Automatically adding devices
[477079.277] (==) Automatically enabling devices
[477079.277] (==) Automatically adding GPU devices
[477079.277] (==) Max clients allowed: 256, resource mask: 0x1fffff
[477079.277] (WW) `fonts.dir' not found (or not valid) in "/usr/share/fonts/75dpi/".
[477079.277]    Entry deleted from font path.
[477079.277]    (Run 'mkfontdir' on "/usr/share/fonts/75dpi/").
[477079.277] (==) FontPath set to:
        /usr/share/fonts/misc/,
        /usr/share/fonts/TTF/,
        /usr/share/fonts/OTF/,
        /usr/share/fonts/Type1/,
        /usr/share/fonts/100dpi/
[477079.277] (==) ModulePath set to "/usr/lib/xorg/modules"
[477079.277] (II) The server relies on udev to provide the list of input devices.
        If no devices become available, reconfigure udev or disable AutoAddDevices.
[477079.277] (II) Loader magic: 0x819d20
[477079.277] (II) Module ABI versions:
[477079.277]    X.Org ANSI C Emulation: 0.4
[477079.277]    X.Org Video Driver: 20.0
[477079.277]    X.Org XInput driver : 22.1
[477079.277]    X.Org Server Extension : 9.0
[477079.278] (++) using VT number 7

[477079.278] (II) systemd-logind: logind integration requires -keeptty and -keeptty was not provided, disabling logind integration
[477079.278] (II) xfree86: Adding drm device (/dev/dri/card0)
[477079.279] (EE) /dev/dri/card0: failed to set DRM interface version 1.4: Permission denied
[477079.279] (--) PCI:*(0:2:0:0) 10de:11c2:1458:356d rev 161, Mem @ 0xf6000000/16777216, 0xe8000000/134217728, 0xf0000000/33554432, I/O @ 0x0000e000/128, BIOS @ 0x????????/524288
[477079.279] (WW) Open ACPI failed (/var/run/acpid.socket) (No such file or directory)
[477079.279] (II) LoadModule: "glx"
[477079.280] (II) Loading /usr/lib/xorg/modules/extensions/libglx.so
[477079.286] (II) Module glx: vendor="NVIDIA Corporation"
[477079.286]    compiled for 4.0.2, module version = 1.0.0
[477079.286]    Module class: X.Org Server Extension
[477079.286] (II) NVIDIA GLX Module  361.28  Wed Feb  3 15:10:57 PST 2016
[477079.286] (==) Matched nouveau as autoconfigured driver 0
[477079.286] (==) Matched nv as autoconfigured driver 1
[477079.286] (==) Matched modesetting as autoconfigured driver 2
[477079.286] (==) Matched fbdev as autoconfigured driver 3
[477079.286] (==) Matched vesa as autoconfigured driver 4
[477079.286] (==) Assigned the driver to the xf86ConfigLayout
[477079.286] (II) LoadModule: "nouveau"
[477079.286] (WW) Warning, couldn't open module nouveau
[477079.286] (II) UnloadModule: "nouveau"
[477079.286] (II) Unloading nouveau
[477079.286] (EE) Failed to load module "nouveau" (module does not exist, 0)
[477079.286] (II) LoadModule: "nv"
[477079.286] (WW) Warning, couldn't open module nv
[477079.286] (II) UnloadModule: "nv"
[477079.286] (II) Unloading nv
[477079.286] (EE) Failed to load module "nv" (module does not exist, 0)
[477079.286] (II) LoadModule: "modesetting"
[477079.287] (II) Loading /usr/lib/xorg/modules/drivers/modesetting_drv.so
[477079.287] (II) Module modesetting: vendor="X.Org Foundation"
[477079.287]    compiled for 1.18.3, module version = 1.18.3
[477079.287]    Module class: X.Org Video Driver
[477079.287]    ABI class: X.Org Video Driver, version 20.0
[477079.287] (II) LoadModule: "fbdev"
[477079.287] (WW) Warning, couldn't open module fbdev
[477079.287] (II) UnloadModule: "fbdev"
[477079.287] (II) Unloading fbdev
[477079.287] (EE) Failed to load module "fbdev" (module does not exist, 0)
[477079.287] (II) LoadModule: "vesa"
[477079.287] (WW) Warning, couldn't open module vesa
[477079.287] (II) UnloadModule: "vesa"
[477079.287] (II) Unloading vesa
[477079.287] (EE) Failed to load module "vesa" (module does not exist, 0)
[477079.287] (II) modesetting: Driver for Modesetting Kernel Drivers: kms
[477079.287] (WW) Falling back to old probe method for modesetting
[477079.287] (EE) Screen 0 deleted because of no matching config section.
[477079.287] (II) UnloadModule: "modesetting"
[477079.287] (EE) Device(s) detected, but none match those in the config file.
[477079.287] (EE)
Fatal server error:
[477079.287] (EE) no screens found(EE)
[477079.287] (EE)
Please consult the The X.Org Foundation support
         at http://wiki.x.org
 for help.
[477079.287] (EE) Please also check the log file at "/var/log/Xorg.6.log" for additional information.
[477079.287] (EE)
[477079.420] (EE) Server terminated with error (1). Closing log file.