How to resolve screen flickering on Ubuntu 14.04 LTS and Dell Inspiron 15 7000 Series 7548
The monitor can go into a flickering mode which is easily triggered by going into "Search your computer and online sources." It is especially bad if other applications are open like Chrome (perhaps opengl related). It can go into a loop that will get so bad that a reboot is necessary. It is not reliable.
I have tried disabling (in compiz-settings-manager) "Unredirect Fullscreen Windows." Also tried increasing the "Launcher reveal Pressure."
So far, since I have only seen this triggered by using the "Search your computer and online sources," I'm wondering if there is a second interface (perhaps text only) that users can use until there is fix..
In the mean time, I have made it stable by decreased the display resolution from 3840 x 2160 to 1920 x 1080.
EDIT:
lspci | grep VGA 00:02.0 VGA compatible controller: Intel Corporation Broadwell-U Integrated Graphics (rev 09) 08:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Opal XT [Radeon R7 M265] (rev ff)
Possibly related: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1407913
Try going into CompizConfig Settings Manager and searching for workarounds.
Click on the only result:
then scroll down to the bottom and select the Force full screen redraws (buffer swap) on repaint check box:
Close CompizConfig and reboot and see if this helps.
This resolved a screen flicker I was having with my NVIDIA GTX 750 Ti, so I'm not totally sure it will work, seeing as you don't give your GPU (if any.)
However, it never hurts (well, normally) to share - hope this helps :)
I had the same problem with this computer running Fedora 21 and Gnome shell at 3840x2160. I came across this discussion that lead me to the solution. https://bugs.freedesktop.org/show_bug.cgi?id=83497. Passing the option i915.enable_ips=0 to the kernel upon boot completely solved the problem for me.
This is a kernel problem that was fixed on 6-4-15 (see link that knutsondc provided). I have the same machine and problem. I was able to solve the problem by installing a unstable kernel image from http://kernel.ubuntu.com/~kernel-ppa/mainline/drm-intel-nightly/ (i used the 6-25 image). After installing the kernel the search, chrome, and keepass2 no longer have the blackout or flickering. The OS now freezes if I change the zoom level, but if I reboot the new zoom holds. So after all that I have 4k video in Ubuntu for now.