Laptop LCD screen does not turn off when inactive in Kubuntu 8.10

I am having the same problem -- XFCE or Gnome will correctly turn my backlight off, but KDE will not. This started with KDE4; KDE3 used to work fine. I'm using a Dell Vostro 1400 with the Nvidia 8400 card. Doesn't matter whether I use the proprietary Nvidia driver or the VESA driver (same result). xset -q shows:

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

So oddly it looks like KDE is setting X correctly. Let me know if other info would be helpful.

Marc

I note also that the backlight turns off fine when waiting at the login screen: it's just when logged into KDE4 that the screen fails to turn off.

xset -q gives similar results for me, so I agree it doesn't look like an X config issue...

Just took a look on the KDE bug site, and this has been reported. If you set the power management pref to turn the screen off BEFORE the screensaver blanks the screen (and locks it), then everything works!

Can you give a link? I found the bug reported -- https://bugs.kde.org/show_bug.cgi?id=180104 -- but not the workaround you note.

Further update -- I tried the workaround you suggest; it doesn't work for me. The screen powers off and then immediately the backlight comes back on again. This is a problem that has also existed with earlier versions of KDE -- see e.g. https://bugs.kde.org/show_bug.cgi?id=174024

Joe: It's this bug: <https://bugs.kde.org/show_bug.cgi?id=165368>. I changed my settings to this: the blank screensaver is set to go off after 6 minutes. In the power tab of the monitor settings, I have the last item (turn screen off) set to 5 minutes and the other two set to disabled. This is working consistently for me.

I don't think the issue is KDE specific.
I am running Ubuntu 8.10 on a HP Pavillion and have the same problem.
This was true also in Ubuntu 8.04 and earlier.
The suggested workaround is working also in gnome !

Unfortunately the workaround doesn't work for me ... :-( The screen does turn off, but after about 5 seconds flicks back on again.

Interesting that it's showing up in GNOME on at least some systems. That's certainly consistent with our observations here that the X power settings are correct.

This kind of problem has been recurring for various people with various Linux distros over the last years, so it may be a regression of some sort ...

Should be fixed in KDE 4.3. (Kubuntu 9.10)

Hi all, I'm on Oneric with Kubuntu 11.10 and I am seeing this bug still. The automatic screen off on laptop lid close functionality does not work if the screensaver is set to automatically turn on. The workaround is ok for me for now, but I think this may be a regression. Please let me know if I can contribute any particular information.