White screens in Aspire E15 E5-521-44NP

[Antonio Pardo-Cayuela]

Hello everybody,

I would be very grateful if someone could help me to solve the following 
problem:

When I start my laptop with an external monitor switched to it via VGA 
or HDM I get both screens in white. But when I first start the laptop 
computer without the external monitor switched to it and later on I 
switch it to the laptop computer it is not detected by Ubuntu 16.04 
because there is not any VGA nor HDMI video output signal.

I have updated the system to the latest mesa and xorg packages and the 
problems remain the same.

With many thanks and best wishes,

Antonio.