Tried to upgrade to the last BIOS for my machine. Dell 7x80 v 1.5.8.
The kernel has also been upgraded to 4.10.0-33-generic
Still have the same issue. Not that hard to reproduce. Just watch a Youtube clip. I'm feeling lucky if I can watch it to the end.
In addition the last couple of days I have also experienced that the external monitors some times is not detected. It might be if they are not connected at a reboot. That is a new effect that is not wanted