Originally reported in fedora's bugtracker here: https://bugzilla.redhat.com/process_bug.cgi
But I've since moved to ubuntu. The bug is still present, so I thought I should report it here as well.
Description of problem:
Monitor does not standby / turn off, but instead keeps entering and leaving
standby.
How reproducible:
Always.
Steps to Reproduce:
1. xset dpms force off
Actual results:
The monitor goes dark (but not off). A few seconds later, the monitor shows me
an "entering power save mode" message and then actually turns off the
backlight. A second or so after that, the monitor backlight is turned on again,
with a DVI cable symbol in the top left corner as if a cable had just been
plugged in (my computer is connected to my monitor with DVI, and nothing else
is plugged into the monitor). Seconds later, it shows the message about
entering power save mode. This repeats indefinitely.
This also happens using the normal power saving settings, and leaving my
computer alone for 5 minutes.
Expected results:
Monitor should turn off / enter standby until I wake it
ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: linux-image-3.0.0-14-generic 3.0.0-14.23
ProcVersionSignature: Ubuntu 3.0.0-14.23-generic 3.0.9
Uname: Linux 3.0.0-14-generic x86_64
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24.
ApportVersion: 1.23-0ubuntu4
Architecture: amd64
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/controlC0: tim 1914 F.... pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
Card hw:0 'SB'/'HDA ATI SB at 0xfe8f4000 irq 16'
Mixer name : 'Realtek ALC887'
Components : 'HDA:10ec0887,10280458,00100202'
Controls : 36
Simple ctrls : 21
Card1.Amixer.info:
Card hw:1 'Generic'/'HD-Audio Generic at 0xfe9bc000 irq 43'
Mixer name : 'ATI R6xx HDMI'
Components : 'HDA:1002aa01,00aa0100,00100200'
Controls : 4
Simple ctrls : 1
Card1.Amixer.values:
Simple mixer control 'IEC958',0
Capabilities: pswitch pswitch-joined penum
Playback channels: Mono
Mono: Playback [on]
Date: Mon Jan 2 10:20:26 2012
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
MachineType: Dell Inc. Studio XPS 7100
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.0.0-14-generic root=UUID=a60a2291-2148-457f-99c5-94c452dd9fad ro quiet splash vt.handoff=7
RelatedPackageVersions:
linux-restricted-modules-3.0.0-14-generic N/A
linux-backports-modules-3.0.0-14-generic N/A
linux-firmware 1.60
RfKill:
0: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 09/10/2010
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A06
dmi.board.name: 0GK1K2
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 3
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA06:bd09/10/2010:svnDellInc.:pnStudioXPS7100:pvr:rvnDellInc.:rn0GK1K2:rvrA00:cvnDellInc.:ct3:cvr:
dmi.product.name: Studio XPS 7100
dmi.sys.vendor: Dell Inc.
I have the same problem. I don't think it's good for the monitor, so I'll disable power saving for the time being.
My monitor is a "DELL P2411H" (from Xorg.0.log), and the X driver is Radeon. The monitor is connected via the DVI cable. I don't have the problem when I use fglrx, the proprietary AMD driver.
Searching the Redhat bugzilla I assume the equivalent bug is this: https:/