When I logoff the user and expecting to see the logon screen (unity-greeter), my monitor looses the signal and stays black (repeatedly trying someting, but failing).
I can get a terminal with Ctrl+Alt+F1, and after Alt+F7 I have infact my logon screen.
When I was setting up my system, I was facing severe problems with my graphics adapter (NVIDIA GeForce GTX 1660) and the 4k display (3840x2160), due to which I didn't get video signal in Ubuntu installation (see also here).
Also in the lock screen (special+L) I lost video. This I could already fix by this suggestion, but to be honest I didn't know what I was doing there.
Is my NVIDIA driver still not configured correctly?
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 19.10
Release: 19.10
Codename: eoan
Here is some output (motivated from here:
$ nvidia-smi
Sat Apr 18 13:30:20 2020
+-----------------------------------------------------------------------------+
| NVIDIA-SMI 435.21 Driver Version: 435.21 CUDA Version: 10.1 |
|-------------------------------+----------------------+----------------------+
| GPU Name Persistence-M| Bus-Id Disp.A | Volatile Uncorr. ECC |
| Fan Temp Perf Pwr:Usage/Cap| Memory-Usage | GPU-Util Compute M. |
|===============================+======================+======================|
| 0 Graphics Device Off | 00000000:08:00.0 On | N/A |
| 42% 34C P0 34W / 125W | 507MiB / 5910MiB | 1% Default |
+-------------------------------+----------------------+----------------------+
+-----------------------------------------------------------------------------+
| Processes: GPU Memory |
| GPU PID Type Process name Usage |
|=============================================================================|
| 0 13069 G /usr/lib/xorg/Xorg 242MiB |
| 0 13495 G /usr/bin/gnome-shell 259MiB |
| 0 15469 G gnome-control-center 3MiB |
+-----------------------------------------------------------------------------+
$ grep "X Driver" /var/log/Xorg.0.log
[ 794.441] (II) NVIDIA dlloader X Driver 435.21 Sun Aug 25 08:17:08 CDT 2019
Is my driver in the right location?
$ modinfo /usr/lib/modules/$(uname -r)/kernel/drivers/video/nvidia.ko | grep ^version
modinfo: ERROR: Module /usr/lib/modules/5.3.0-46-generic/kernel/drivers/video/nvidia.ko not found.
$ find /usr/lib/modules -name nvidia.ko
/usr/lib/modules/5.3.0-46-generic/updates/dkms/nvidia.ko
$ modinfo /usr/lib/modules/$(uname -r)/updates/dkms/nvidia.ko | grep ^version
version: 435.21
