I upgraded my openSUSE KDE 13.1 install to Tumbleweed and had a kernel update to 3.13. After this change i can no longer use an external monitor.
When plugging in my external monitor my laptop screen turns off and the external monitor goes into powersave. No change is observed after waiting for a 30 seconds or so. I unplug the monitor and my laptop screen turns on again.
Now i suspect this has been caused by the introduction of the new Dynamic Power Management changes for Radeon in the Linux Kernel 3.13 for AMD cards. I have a (painful) hybrid i915/AMD graphics hardware. Nonetheless no other problems have been observed with my graphics card.
Is there a keyboard combination i can press to cycle through the display options to see if the application (KSCREEN?) has just set my display to strange settings?
I’m pretty stumped here.
uname -r
3.13.0-9.g4b6e17a-desktop
lspci | grep VGA
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Seymour [Radeon HD 6400M/7400M Series] (rev ff)
xrandr --listproviders
Providers: number : 2
Provider 0: id: 0x7b cap: 0xb, Source Output, Sink Output, Sink Offload crtcs: 3 outputs: 5 associated providers: 0 name:Intel
Provider 1: id: 0x53 cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 4 outputs: 0 associated providers: 0 name:radeon