Xorg does not starts automatically after its restart

Xorg does not starts after logout or manual killing its process.
It works properly after manual starting (with startx).

I’m using latest version of Tumbleweed (20150330), Gnome-Shell 3.16, proprietary nvidia driver 349.12 and linux 3.19.3.

I noticed that gdm does not works for me, it cannot be started. systemctl returns this error:

$ systemctl status gdm.service
● gdm.service
   Loaded: not-found (Reason: No such file or directory)
   Active: inactive (dead)
# systemctl start gdm.service
Failed to start gdm.service: Unit gdm.service failed to load: No such file or directory.

Since you’re using Nvidia proprietary drivers you might want to check out here:
https://en.opensuse.org/SDB:NVIDIA_the_hard_way

Why do you expect it to be present in the first place?

Guy on G+ told me that this may be a problem. But its not.
Display manager is loaded correctly:

$ systemctl status display-manager.service
● display-manager.service - X Display Manager
   Loaded: loaded (/usr/lib/systemd/system/display-manager.service; disabled; vendor preset: disabled)
   Active: active (running) since Суб 2015-04-04 08:52:41 EEST; 1h 8min ago
  Process: 1337 ExecStart=/usr/lib/X11/display-manager start (code=exited, status=0/SUCCESS)
 Main PID: 1360 (gdm)
   CGroup: /system.slice/display-manager.service
           └─1360 /usr/sbin/gdm

I just installed same version of Tumbleweed on VBox VM and this problems also appears in a VM.