Did this issue start happening after an update/upgrade? Was there a prior kernel version where you were not having this particular problem?
Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.6 kernel[0]. If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'. If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'. Once testing of the upstream kernel is complete, please mark this bug as "Confirmed". Thanks in advance. [0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.6-rc7-wily/ ** Changed in: linux (Ubuntu) Importance: Undecided => Medium ** Changed in: linux (Ubuntu) Status: Confirmed => Incomplete -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1579579 Title: Monitors immediately come out of energy saving mode Status in linux package in Ubuntu: Incomplete Bug description: On Kubuntu 16.04 with kernel 4.4.0-22.39-generic 4.4.8, but it's been like this since 15.10 a few kernels back. Multiple screens connected. Intel i7 4771 Haswell with only integrated GPU (no dedicated graphics card). What happens is that the monitors do enter energy saving mode at the configured timeout of user inactivity, but a couple seconds later they snap right out of it. Usually when I come back to my computer after being away there are also a few Plasma crash dialogs. My monitors haven't been saving energy (or pixel life) in over half a year now. The only evidence I found in the system log, which I'm not sure is related but might be worth mentioning, is: [Mon May 9 00:29:03 2016] snd_hda_codec_hdmi hdaudioC0D0: HDMI: ELD buf size is 0, force 128 [Mon May 9 00:29:03 2016] snd_hda_codec_hdmi hdaudioC0D0: HDMI: invalid ELD data byte 0 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1579579/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
