Version:           4.7 (using KDE 4.7.3) 
OS:                Linux

KDE restores default xrandr settings without checking that these settings can be used.

After configuring a dual head setup with external displays and restarting with single display my internal notebook screen is switched off. 

**** This is a usability nightmare!!!! ****

I analyzed the problem with strace on the system-console and found out that
"$HOME/.kde/share/config/startupconfig" contains settings which are not usable on a internal display setup:
---
krandrrc_display_startupcommands='xrandr --output eDP1 --off
xrandr --output HDMI1 --pos 1680x0 --mode 1680x1050 --refresh 59.9543
xrandr --output HDMI2 --pos 0x0 --mode 1680x1050 --refresh 59.9543
xrandr --output HDMI2 --primary'
---

After removing this line, my system started in a normal way.
xrandr output with a single screen setup:
---
# xrandr
Screen 0: minimum 320 x 200, current 1440 x 900, maximum 8192 x 8192
eDP1 connected 1440x900+0+0 (normal left inverted right x axis y axis) 304mm x 190mm
   1440x900       60.0*+   40.0  
VGA1 disconnected (normal left inverted right x axis y axis)
HDMI1 disconnected (normal left inverted right x axis y axis)
DP1 disconnected (normal left inverted right x axis y axis)
HDMI2 disconnected (normal left inverted right x axis y axis)
DP2 disconnected (normal left inverted right x axis y axis)
---

KDE should check if all necessary displays are connected before(!) executing the xrandr commands.

I cannot understand that good multihead display support can be a problem for so many years. 
Gnome2/Unity seems to have a good solution for changing monitor setups - probably you can implement the same behavior.



Reproducible: Always

Steps to Reproduce:
1.) Startup your notebook system with two external DVI/HDMI displays (disabled notebook screen, dockingstation setup)
2.) configure a dual head setup in systemsettings/display
3.) save setup as default setup
4.) restart notebook without external displays
5.) Login to kde (i used autologin)

=> Screen remains black 


Expected Results:  
KDE should store information about changing monitor setups, and should only restore stored settings if exactly the same monitor setup appears again.
(same outputs connected, same displays connected).
Monitor profiles should be manageable (store,edit,delete).

Doing the same behavior like gnome/unity would be a good improvement.