You should start the X-Window manager only when you really need it

I tend to do a lot of routine tasks from the command line. Most commercial Linux distributions, however, default to starting an X-Window manager following system initialization. That's a lot of system resources to have running.

To change this behavior, edit the /etc/inittab file and locate the line that reads: id:5:initdefault and change it to id:3:initdefault.The system will start with a command line login, and when the need arises to run a window manager, it's easy to simply type startx