Well, personally I can work around the problem by installling the Nvidia blob. But it should be debugged and fixed in the Ubuntu code. Currently I don't even know against which package I should file a bug.
I had a look at the X logs:
[ 170.929] _XSERVTransSocketUNIXCreateListener: ...SocketCreateListener() failed
[ 170.931] _XSERVTransMakeAllCOTSServerListeners: server already running
[ 170.932] (--) Log file renamed from "/var/log/Xorg.pid-1608.log" to "/var/log/Xorg.1.log"
[ 170.934]
That lines are just available in Xorg.1.log but not in Xorg.0.log. Might those give a clue?
My specs...
Code:
System: Host: amano-desktop Kernel: 4.13.0-16-generic x86_64
bits: 64 gcc: 7.2.0
Desktop: Gnome 3.26.1 (Gtk 3.22.21-0ubuntu1)
Distro: Ubuntu Artful Aardvark (development branch)
Machine: Device: desktop Mobo: ASRock model: AMCP7A-ION serial: N/A
BIOS: American Megatrends v: P1.60 date: 08/26/2009
CPU: Dual core Intel Atom 330 (-HT-MCP-)
arch: Bonnell rev.2 cache: 512 KB
flags: (lm nx sse sse2 sse3 ssse3) bmips: 6399
clock speeds: max: 1599 MHz 1: 1599 MHz 2: 1599 MHz 3: 1599 MHz
4: 1599 MHz
Graphics: Card: NVIDIA ION VGA bus-ID: 01:00.0
Display Server: wayland (X.Org 1.19.5 )
drivers: nvidia (unloaded: modesetting,fbdev,vesa,nouveau)
Resolution: 1440x900@59.75hz
OpenGL: renderer: NVAC version: 3.3 Mesa 17.2.2 Direct Render: Yes
Audio: Card NVIDIA MCP79 High Def. Audio
driver: snd_hda_intel bus-ID: 00:08.0
Sound: Advanced Linux Sound Architecture v: k4.13.0-16-generic
Network: Card: NVIDIA MCP79 Ethernet
driver: forcedeth port: d080 bus-ID: 00:0a.0
IF: enp0s10 state: up speed: 100 Mbps duplex: full mac: <filter>
Drives: HDD Total Size: 320.1GB (47.3% used)
ID-1: /dev/sda model: ST9320325AS size: 320.1GB temp: 46C
Partition: ID-1: / size: 21G used: 14G (69%) fs: ext4 dev: /dev/sda5
ID-2: swap-1 size: 1.03GB used: 0.00GB (0%)
fs: swap dev: /dev/sda6
RAID: No RAID devices: /proc/mdstat, md_mod kernel module present
Sensors: System Temperatures: cpu: 77.0C mobo: N/A gpu: 81.0
Fan Speeds (in rpm): cpu: N/A
Info: Processes: 227 Uptime: 39 min Memory: 1605.8/3256.5MB
Init: systemd runlevel: 5 Gcc sys: 7.2.0
Client: Shell (bash 4.4.121) inxi: 2.3.3
As an attachment my gnome-logs file (though showing the current session that I was able to start):