Laptop screen blank when HDMI connected at boot

[Jamie Kitson]

Hi,

I have an issue whereby when I leave my HDMI monitor connected to my
Asus Zenbook UX31E at boot the laptop screen never comes on. X thinks
that it is on as I can move windows and the mouse cursor into that
region but I cannot bring it on. I am not sure how to investigate this
any further. xrandr reports that the monitor is on and at its default
resolution but does not bring it on.

Thanks, Jamie