DPMS Turns Itself On

[Snowhog]

Nice post. I've copied to our How To's board.

Welcome to KFN!

Hi,

I installed kubuntu 12.04.1, earlier today and run into this bug and stumbled across this thread looking for a solution. I believe I have figured out a workaround for now (for those who don't want to compile KDE from source and don't mind disabling power management completely), so I thought I'd post it here, since I haven't seen it anywhere else.

THE BUG: performing some actions such as (un)installing a package in muon cause dpms to be enabled overriding kde power management settings (others have reported using dragon or vlc or copying a file with dolphin can trigger the problem, I believe). xset -q reveals dpms has been switched on with apparently random setting for Standby, Suspend and Off. xset -dpms will temporarily fix this, until the bug is activated again (e.g. through muon).

THE WORKAROUND:

1) Go to System settings > Startup and Shutdown > Service Manager and disable Power Managment

2) Create the following script (similar to one proposed earlier in the thread):

#!/bin/bash

xset dpms 0 0 0
xset -dpms

name it "nodpms" (say) and chmod +x it and move it to ~/.kde/Autostart. Then logout and in again, and the fix should be in place. Installing a package in muon no longer enables dpms. Note: You need this script otherwise dpms defaults to on at login, but I guess disabling dpms in xorg.conf instead of the above script will probably have the same effect, but I've not tried it.

Hope this helps someone else.

[Mr_Bumpy]

I can confirm that running Muon causes DPMS to be re-enabled. This seems to happen during the process where Muon tells Solid to supress sleep/monitor blanking while it does its updates. The bug is probably in Solid and appears to be fixed in current KDE GIT (although I can't confirm this). Here are the related KDE bug reports: #306490, #295164. At the bottom of the second link there is a review request that should fix the problem.

[Dutchman]

It could be a bug in the kernel modules 'acpi' and/or 'apm' or the daemons that work with them, acpid and/or apmd. You can find out by temporarily disabling them.

Reboot the machine, and when the grub menu appears, press "e" to edit the boot configuration. On Ubuntu-based distros you may have to hold down the SHIFT key after the computer's POST messages to get to the grub menu, keep SHIFT held down until you see the menu. Don't worry, what you change here will only apply until the next reboot. Once in the edit screen, find the line that starts with "linux" and has things like "ro splash quiet" and other stuff in it. Move the cursor over to somewhere after "ro" and type in:

acpi=off

or if on a laptop:

noapm

Then press F10 to continue booting. If your screen blanking stops, you've found what's triggering it. Note though that these modules control other power features too, so you may need to keep an eye on your system behavior to see if anything else goes a bit wonky before adding it permanently to /boot/grub/grub.cfg. It also wouldn't hurt to open a terminal and run "dmesg | less" to look at the system log to see if anything is having problems because of these modules being turned off.

You can find info on these modules in your '/usr/share/doc/' folder that may be of some help.

[SteveRiley]

Try out Smplayer+Mplayer2 combo, works much better for me than Vlc.

I'm also using this combination now. I tried many GUI front-ends for MPlayer; SMPlayer is the only one I could find that passes the left-bracket and right-bracket keys to MPlayer to speed up or slow down playback.

[Shimapan]

EDIT: I think it might actually be VLC that's resetting DPMS.

Hooray for Vlc! XD
Try out Smplayer+Mplayer2 combo, works much better for me than Vlc.

[Zeikcied]

DPMS seems to be resetting itself when I view videos in Firefox. Both Flash and HTML5. But it doesn't seem like it's every time.

Does this nonsense happen in GNOME or Unity, or any other KDE-based distro? I'm really getting tired of dealing with this.

EDIT: I think it might actually be VLC that's resetting DPMS.

[GreyGeek]

I go the other route, set the blanking to far into the future ... 32000 seconds...

xset dpms 32000 32000 32000
xset s noblank
xset -dpms

[Zeikcied]

#!/bin/sh
#
# no sleep display

xset -dpms;

xset s off

setterm -blank 0 -powerdown 0


exit 0
-----------------------------
copy this into your favorite text editor and save it to /home/your user name/.kde/Autostart
make it executable
reboot

This has worked for a while, but after recent updates, it's gotten a lot worse. DPMS is now turning itself on and resetting itself to default values extremely frequently, and I don't know what the cause is.

[slopechz50]

Just tried this. I thought this issue was resolved, but Ubuntu did update the kernel yesterday. I have no idea if that is the issue that has started this problem again. Thank you.

#!/bin/sh
#
# no sleep display

xset -dpms;

xset s off

setterm -blank 0 -powerdown 0


exit 0
-----------------------------
copy this into your favorite text editor and save it to /home/your user name/.kde/Autostart
make it executable
reboot

[JustinBailey]

Thanks! Is there anything else I need to do? I tried the script out, but it seems to be sleeping even more now.

On the other hand, I can go to System Settings > Power Management > Energy Saving Settings and check the box next to Screen Energy Saving, and then set the time as high as it will go (360 min). Since I don't think I'll ever be watching anything for 6 hours straight, this seems like a reasonable workaround.

[davidw1957]

#!/bin/sh
#
# no sleep display

xset -dpms;

xset s off

setterm -blank 0 -powerdown 0


exit 0
-----------------------------
copy this into your favorite text editor and save it to /home/your user name/.kde/Autostart
make it executable
reboot

[whatthefunk]

Dragon Player is causing DPMS to turn on on my system. Its happened a couple times where I turn DPMS off, watch a video and as soon as I close Dragon Player, the screen blanks.

It also seems that messing with DPMS breaks power management. Power management on my system is as useful as a coprolite.

[slopechz50]

Can someone explain how to do this? I don't think I did it correctly.

xset dpms 0 0 0

stopped the blanking. I put that command into ~/.bash_profile

[slopechz50]

I have the same problem and look forward to a possible resolution!