Yesterday (14.08.2018), a popup on Ubuntu 16.04 showed up and suggested to upgrade to 18.04. After upgrading ( it took several hours), I rebooted the laptop (ASUS U36S) and it showed the black screen with some notices about services.
The last one is different on every boot: currently it is “Started Network Manager Script Dispatcher”. Then it eventually said that “Core/Package temperature above threshold.”. How to fix it?
Here is yet another trial to boot: