No output to external monitor via display port (and docking station)

Since my upgrade from ubuntu 16.04 to 17.10 the output to an external monitor via docking station and displayport doesn't work anymore.

I can activate the external monitor via arandr (from xmonad) but there is no output.

Disper is not working anymore (segmentation fault).

The external monitor works with nvidia-340 drivers.

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: xserver-xorg-video-nouveau 1:1.0.15-2
ProcVersionSignature: Ubuntu 4.13.0-16.19-generic 4.13.4
Uname: Linux 4.13.0-16-generic x86_64
ApportVersion: 2.20.7-0ubuntu3
Architecture: amd64
BootLog:
 /dev/mapper/sda3_crypt: recovering journal
 /dev/mapper/sda3_crypt: clean, 1105421/8855552 files, 30688210/35399936 blocks
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
Date: Tue Oct 17 07:47:40 2017
DistUpgraded: 2017-10-16 20:56:53,501 DEBUG Running PostInstallScript: './xorg_fix_proprietary.py'
DistroCodename: artful
DistroVariant: ubuntu
DkmsStatus:
 virtualbox, 5.1.28, 4.10.0-37-generic, x86_64: installed
 virtualbox, 5.1.28, 4.13.0-16-generic, x86_64: installed
ExtraDebuggingInterest: Yes
GraphicsCard:
 Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: Lenovo 3rd Gen Core processor Graphics Controller [17aa:21f5]
 NVIDIA Corporation GK107GLM [Quadro K2000M] [10de:0ffb] (rev a1) (prog-if 00 [VGA controller])
   Subsystem: Lenovo GK107GLM [Quadro K2000M] [17aa:21f5]
InstallationDate: Installed on 2016-05-18 (516 days ago)
InstallationMedia: Lubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420)
MachineType: LENOVO 2447KD9
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.13.0-16-generic root=UUID=c2a0eb56-8f89-4a8a-b1b5-a152dfaec126 ro quiet splash acpi=force vt.handoff=7
SourcePackage: xserver-xorg-video-nouveau
UpgradeStatus: Upgraded to artful on 2017-10-16 (0 days ago)
dmi.bios.date: 09/18/2015
dmi.bios.vendor: LENOVO
dmi.bios.version: G5ETA3WW (2.63 )
dmi.board.asset.tag: Not Available
dmi.board.name: 2447KD9
dmi.board.vendor: LENOVO
dmi.board.version: Not Defined
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvrG5ETA3WW(2.63):bd09/18/2015:svnLENOVO:pn2447KD9:pvrThinkPadW530:rvnLENOVO:rn2447KD9:rvrNotDefined:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.family: ThinkPad W530
dmi.product.name: 2447KD9
dmi.product.version: ThinkPad W530
dmi.sys.vendor: LENOVO
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.83+git20170928.7c711886-0ubuntu0ricotz~16.04.1
version.libgl1-mesa-dri: libgl1-mesa-dri 17.2.2-0ubuntu1
version.libgl1-mesa-glx: libgl1-mesa-glx 17.2.2-0ubuntu1
version.xserver-xorg-core: xserver-xorg-core 2:1.19.5-0ubuntu2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.5-1ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.10.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20170309-0ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-2
xserver.bootTime: Tue Oct 17 07:38:48 2017
xserver.configfile: default
xserver.errors:
 Failed to load module "nvidia" (module does not exist, 0)
 Failed to load module "nvidia" (module does not exist, 0)
 NOUVEAU(G0): [XvMC] Failed to initialize extension.
xserver.logfile: /var/log/Xorg.0.log
xserver.version: 2:1.19.5-0ubuntu2
xserver.video_driver: modeset