On the boot issue, I also experience the problem that X doesn't start with external monitors plugged in. I'm running Kubuntu 16.10, upgraded from 16.04.
Kernel: 4.8.0-26
I have two external monitors connected to my laptop, one VGA, one HDMI. Whether or not I have the laptop lid open, if the external monitors are plugged in, X won't start. To get things going, I have to issue sudo service sddm start from a terminal. Then all is fine.
On the boot issue, I also experience the problem that X doesn't start with external monitors plugged in. I'm running Kubuntu 16.10, upgraded from 16.04.
Kernel: 4.8.0-26
I have two external monitors connected to my laptop, one VGA, one HDMI. Whether or not I have the laptop lid open, if the external monitors are plugged in, X won't start. To get things going, I have to issue sudo service sddm start from a terminal. Then all is fine.