Adding dual monitor is very slow

[Guest]

After upgrading to Vivid, I have an issue when adding an external monitor.
It takes ages (a few mnutes), before Kubuntu configures itself with the 2nd monitor. During this configuration, the system is not responsive at all.
I have an Intel i7 processor and normally the system is very quick.
After the configuration phase, everything works again at normal speed

[ronw]

I'm seeing the same thing here -- at least 2 - 3 minutes where the system is almost non-responsive when opening or closing the laptop lid.

Playing with the new "Even when an external monitor is connected" setting in power management.

Also just realized I added the backports PPA yesterday, but not the beta one. Looking forward to the PPA situation settling down and some of the extraneous ones disappearing.