Cannot start gdm3 with nvidia drivers in use

[shinyblue]

When using nvidia-361 drivers gdm will not start, whereas lightdm will start (and is able to launch a gnome DE session).

I get a blank screen. Sometimes it cycles between blank and then flash to tty and back again and again.

I am reporting here after reading the 'where to report a bug' page on the ubuntu wiki, but the following Xorg bug may be related https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1559304

If I use prime-select intel then I can start GDM.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: gdm3 3.18.3-0ubuntu2
ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6
Uname: Linux 4.4.0-21-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia_modeset nvidia
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
Date: Mon Apr 25 10:20:26 2016
InstallationDate: Installed on 2016-04-22 (3 days ago)
InstallationMedia: Ubuntu-GNOME 16.04 LTS "Xenial Xerus" - Beta amd64 (20160323.1)
ProcEnviron:
 LANGUAGE=en_GB:en
 TERM=linux
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: gdm3
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Christoph (kick-christoph)]

Can confirm.

I've got exactly the same problem with gdm.

"gnome-session-is-accelerated: No hardware 3D support" is the only hint I've found

[Christoph (kick-christoph)]

Here is my systemd journal