If your like me and are not a fan of the gui login screen that ubuntu uses or you want to reduce resource usage you can do the following to disable the gui login and rather use a console login instead.
echo "manual" | sudo tee -a /etc/init/lightdm.override
You can also do this with GDM
echo “manual” | sudo tee -a /etc/init/gdm.override
This prevents the desktop manager from loading it’s service, you will now either need to start lightdm manually or have a different window manager installed because with out lightdm being started unity will not work. You can restart lightdm by doing the following
sudo service lightdm start
I personally use XFCE rather than lightdm since it uses less resources, you can edit the ..xinitrc file in your home directory to change which window manager you are using. If you do not have another window manager installed please read Changing Window Managers, which will guide you through the installation process.
If the file .xinitrc is not in your home directory create the file and chmod +x .xinitrc
In the .xinitrc you will find a line like
#!/usr/bin/env bash exec xfce-se
You will change this to whichever window manager you would like to use.
I’ve listed a few available window manager
WM=gnome-session WM=startkde WM=afterstep WM=wmaker WM=enlightenment WM=blackbox WM=icewm
Once you have finished when you reboot you will be greeted with a text login prompt and can use startx to start your xsession.
No sound after rebooting into XFCE or other window manager read No Sound After Installing XFCE/Xubuntu