I'm using Linux Mint 19. When I start computer screen goes off when password is asked. I have reinstalled gdm3 but it didn't worked. After installing wdm computer screen donesn't hang or go off. But I want to keep gdm. I need your help. Shukariya.
Try using a different display manager — LightDM [is the default](https://forums.linuxmint.com/viewtopic.php?t=286386) for Cinnamon, and you may also have some joy with mdm, according to [this thread](https://forums.linuxmint.com/viewtopic.php?t=261704):
sudo apt-get install mdm
sudo dpkg-reconfigure mdm