This was a problem in 17.10 and it's carried over to 18.04 and at this point it's driving me nuts.
My screen keeps blanking after one minute of idle. I cannot even read articles.
In Gnome settings, Privacy > Lock screen is off, and I've set Power > Blank Screen to Never and Automatic Suspend is set to Off
What else do I need to disable? I'll decide when my screen is locked. I just want all of it off.
Update
Additional things I've checked and ruled out:
I've installed Dconf Editor and checked the settings there and I'm unable to find anything that changes the behaviour. I tried disabling the idle-dim setting under /org/gnome/settings-daemon/plugins/power and tried just disabling the entire power plugin, neither change has had an effect on the behaviour.
I've also combed through the nvidia-settings app and cannot find anything related to power or screen blanking there. My xorg server is using the out-of-the-box auto-detection for startup and there is no xorg.conf setting anything on my system. This is all just default 18.04 behaviour for me.
Found this question and checked the xset q output, adding it. You'll note that my timeout and cycle settings are at 0 which was the solution there, however mine are already set to 0 and my screen is still blanking. That question is for Unity anyway and mine is for Gnome3
routhinator@chris-desktop:~$ xset q
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: 500 repeat rate: 33
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: 0
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 Enabled
Monitor is On
Update No. 2
As per @WinEunuuchs2Unix I have inspected, changed, and reinspected the settings in this question and the issue is still persisting.
On another note, these settings needing to be changed manually like this seems to be a long standing bug that Ubuntu should have fixed long ago, because are these are the exact settings I thought I turned off above in the power settings.
routhinator@chris-desktop:~$ gsettings get org.gnome.settings-daemon.plugins.power sleep-inactive-battery-timeout
1800
routhinator@chris-desktop:~$ gsettings get org.gnome.settings-daemon.plugins.power sleep-inactive-ac-timeout
3600
routhinator@chris-desktop:~$ gsettings get org.gnome.desktop.screensaver idle-activation-enabled
true
routhinator@chris-desktop:~$ gsettings get org.gnome.settings-daemon.plugins.power idle-dim
true
routhinator@chris-desktop:~$ gsettings set org.gnome.settings-daemon.plugins.power sleep-inactive-battery-timeout 0
routhinator@chris-desktop:~$ gsettings set org.gnome.settings-daemon.plugins.power sleep-inactive-ac-timeout 0
routhinator@chris-desktop:~$ gsettings set org.gnome.desktop.screensaver idle-activation-enabled false
routhinator@chris-desktop:~$ gsettings set org.gnome.settings-daemon.plugins.power idle-dim false
routhinator@chris-desktop:~$ gsettings get org.gnome.settings-daemon.plugins.power sleep-inactive-battery-timeout
0
routhinator@chris-desktop:~$ gsettings get org.gnome.settings-daemon.plugins.power sleep-inactive-ac-timeout
0
routhinator@chris-desktop:~$ gsettings get org.gnome.desktop.screensaver idle-activation-enabled
false
routhinator@chris-desktop:~$ gsettings get org.gnome.settings-daemon.plugins.power idle-dim
false
Update 3
lspci output as requested:
routhinator@chris-desktop:~$ lspci
00:00.0 Host bridge: Intel Corporation 5520/5500/X58 I/O Hub to ESI Port (rev 13)
00:01.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 1 (rev 13)
00:02.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 2 (rev 13)
00:03.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 3 (rev 13)
00:07.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 7 (rev 13)
00:14.0 PIC: Intel Corporation 7500/5520/5500/X58 I/O Hub System Management Registers (rev 13)
00:14.1 PIC: Intel Corporation 7500/5520/5500/X58 I/O Hub GPIO and Scratch Pad Registers (rev 13)
00:14.2 PIC: Intel Corporation 7500/5520/5500/X58 I/O Hub Control Status and RAS Registers (rev 13)
00:14.3 PIC: Intel Corporation 7500/5520/5500/X58 I/O Hub Throttle Registers (rev 13)
00:19.0 Ethernet controller: Intel Corporation 82567V-2 Gigabit Network Connection
00:1a.0 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #4
00:1a.1 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #5
00:1a.2 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #6
00:1a.7 USB controller: Intel Corporation 82801JI (ICH10 Family) USB2 EHCI Controller #2
00:1b.0 Audio device: Intel Corporation 82801JI (ICH10 Family) HD Audio Controller
00:1c.0 PCI bridge: Intel Corporation 82801JI (ICH10 Family) PCI Express Root Port 1
00:1c.4 PCI bridge: Intel Corporation 82801JI (ICH10 Family) PCI Express Root Port 5
00:1d.0 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #1
00:1d.1 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #2
00:1d.2 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #3
00:1d.7 USB controller: Intel Corporation 82801JI (ICH10 Family) USB2 EHCI Controller #1
00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev 90)
00:1f.0 ISA bridge: Intel Corporation 82801JIR (ICH10R) LPC Interface Controller
00:1f.2 IDE interface: Intel Corporation 82801JI (ICH10 Family) 4 port SATA IDE Controller #1
00:1f.3 SMBus: Intel Corporation 82801JI (ICH10 Family) SMBus Controller
00:1f.5 IDE interface: Intel Corporation 82801JI (ICH10 Family) 2 port SATA IDE Controller #2
01:00.0 IDE interface: Marvell Technology Group Ltd. Device 91a3 (rev 11)
02:00.0 USB controller: NEC Corporation uPD720200 USB 3.0 Host Controller (rev 03)
03:00.0 VGA compatible controller: NVIDIA Corporation GK106 [GeForce GTX 660] (rev a1)
03:00.1 Audio device: NVIDIA Corporation GK106 HDMI Audio Controller (rev a1)
04:00.0 VGA compatible controller: NVIDIA Corporation GK107 [GeForce GTX 650] (rev a1)
04:00.1 Audio device: NVIDIA Corporation GK107 HDMI Audio Controller (rev a1)
05:00.0 FireWire (IEEE 1394): VIA Technologies, Inc. VT6315 Series Firewire Controller (rev 01)
ff:00.0 Host bridge: Intel Corporation Xeon 5500/Core i7 QuickPath Architecture Generic Non-Core Registers (rev 05)
ff:00.1 Host bridge: Intel Corporation Xeon 5500/Core i7 QuickPath Architecture System Address Decoder (rev 05)
ff:02.0 Host bridge: Intel Corporation Xeon 5500/Core i7 QPI Link 0 (rev 05)
ff:02.1 Host bridge: Intel Corporation Xeon 5500/Core i7 QPI Physical 0 (rev 05)
ff:03.0 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller (rev 05)
ff:03.1 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Target Address Decoder (rev 05)
ff:03.4 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Test Registers (rev 05)
ff:04.0 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Channel 0 Control Registers (rev 05)
ff:04.1 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Channel 0 Address Registers (rev 05)
ff:04.2 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Channel 0 Rank Registers (rev 05)
ff:04.3 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Channel 0 Thermal Control Registers (rev 05)
ff:05.0 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Channel 1 Control Registers (rev 05)
ff:05.1 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Channel 1 Address Registers (rev 05)
ff:05.2 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Channel 1 Rank Registers (rev 05)
ff:05.3 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Channel 1 Thermal Control Registers (rev 05)
ff:06.0 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Channel 2 Control Registers (rev 05)
ff:06.1 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Channel 2 Address Registers (rev 05)
ff:06.2 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Channel 2 Rank Registers (rev 05)
ff:06.3 Host bridge: Intel Corporation Xeon 5500/Core i7 Integrated Memory Controller Channel 2 Thermal Control Registers (rev 05)
Best Answer
I also had issues with this happening, on a machine that has Ubuntu 18.04 Desktop installed, but is in fact being used as a server. As such the screen blanked, and wouldn't come back. Eventually, I figured out that it was actually caused by the sleep settings kicking in.
Since the machine used LXDE, and didn't have Gnome installed at all, none of the suggestions that I found mentioning gsettings etc. could be used. Eventually I was led to the sleep settings, independent of the login/window manager in use.
So, in addition to the gsettings solutions listed in prior posts, test this solution by disabling the sleep service, and see if it removes the problem:
To undo the change:
For what it is worth, I also disabled suspend.target, hibernate.target and hybrid-sleep.target to prevent any unwanted behaviour.