DPMS not working

[Casshern]

Hi

I built a new machine and installed Kubuntu 22.04 from scratch. Installation was flawless.

But then I noticed the display wont go to standby after hitting the time given in Energy-settings. When booting the machine it has this state:

Machine:
Type: Desktop Mobo: Gigabyte model: B550I AORUS PRO AX v: x.x
serial: <superuser required> UEFI: American Megatrends LLC. v: F16d
date: 05/11/2022
Graphics:
Device-1: NVIDIA GA104 [GeForce RTX 3060 Ti Lite Hash Rate] driver: nvidia
v: 510.73.05
Display: x11 server: X.Org v: 1.21.1.3 driver:X:loaded: nvidia
gpu: nvidia resolution: 2560x1440~75Hz
OpenGL:renderer: NVIDIA GeForce RTX 3060 Ti/PCIe/SSE2
v: 4.6.0 NVIDIA 510.73.05
BOOT_IMAGE=/boot/vmlinuz-5.15.0-33-generic root=UUID=28b7ece9-c277-4830-8d33-a1ba9bc082cb ro acpi_osi=Linux quiet splash vt.hand
off=7
Keyboard Control:
auto repeat: on key click percent: 0 LED mask: 00000002
XKB indicators:
00: Caps Lock: off 01: Num Lock: on 02: Scroll Lock: off
03: Compose: off 04: Kana: off 05: Sleep: off
06: Suspend: off 07: Mute: off 08: Misc: off
09: Mail: off 10: Charging: off 11: Shift Lock: off
12: Group 2: off 13: Mouse Keys: off
auto repeat delay: 600 repeat rate: 25
auto repeating keys: 00ffffffdffffbbf
fadfffefffedffff
9fffffffffffffff
fff7ffffffffffff
bell percent: 50 bell pitch: 400 bell duration: 100
Pointer Control:
acceleration: 2/1 threshold: 4
Screen Saver:
prefer blanking: yes allow exposures: yes
timeout: 0 cycle: 600
Colors:
default colormap: 0x20 BlackPixel: 0x0 WhitePixel: 0xffffff
Font Path:
/usr/share/fonts/X11/misc,/usr/share/fonts/X11/Type1,built-ins
DPMS (Energy Star):
Standby: 0 Suspend: 0 Off: 0
DPMS is Disabled

So DPMS is disabled and Standbytime is Zero (Zero disables Standby even if DPMS is enabled).

So I tried different solutions with no success: Scripts in autostart etc.

If I go to the console and type

xset dpms 600

the result is:

DPMS (Energy Star):
Standby: 600 Suspend: 0 Off: 0
DPMS is Enabled
Monitor is On

Problems:
1. I can't get this command into autostart working. Tried as script or .desktop.
2. Even more weird: When Standby time is reached the monitor goes to standby. After a few seconds it wakes up again and the standby timer restarts.

Where can I search for a solution?

[claydoh]

A couple of weeks ago I was having the same issue with a refurbished Gigabyte motherboard, on a new build.
That board ended up having other issues, so i swapped it for a new Asrock board. No issues with DPMS there

Anyway, I never did track down why, but I suspect it may have been something to do with the BIOS settings, before other problems cause me to replace the board
This was using an AMD GPU, I wonder if it is an Nvidia/xorg.conf setting?

One quick thing to try is to disable Kscreen2 and see if that has any effect on your next reboot:

System Settings >> Startup and Shutdown >> Background services

You will lose the monitor configuration in System Settings, but you may not need this at all, and Kscreen may be keeping the screen awake

[Casshern]

claydoh Thank you for your reply.

I went to System Settings >> Startup and Shutdown >> Background services and disabled KScreen2. This time the monitor stayed in standby. So this might the direction I have to look into. Although then I noticed another weird behavior: The indicator LED of the monitor stayed orange, but the backlight came up after some seconds and went off again after some seconds. And this goes on and on.

[Casshern]

claydoh

Ok, as for now the problem seems solved

After disabling KScreen2 from "System Settings >> Startup and Shutdown >> Background services" the monitor goes to sleep and stays sleeping.

The backlight issue is solved as well. It happens when connecting via Displayport. Reason maybe that the DP-cable (provided with the Acer monitor!) has a wired pin 20 which is not allowed (danger of short circuit). But before buying another cable to check this out I switched to HDMI-connection.

So, once again, thank you for your support