How to run GUI on CentOS 7?

Question

User interface

I decided to put centos under a virtual machine as a client. Here is the latest release.
Installed X Window System, Gnome, wanted to edit etc/inittab, but it says it's no longer in use.
startx doesn't work:

xinit: connectionton X server lost
waiting for x server to shut down error setting MTRR (base = 0xdooooooo, size = 0x00c00000, type = 1) Invalid argument (22)

I did not find any intelligible documentation for the seven.
What do you suggest?

Answer 1

xorg configure - there was some such command and it collected settings for the system. But the last time I did it was 4 years ago. but suddenly you will be prompted to a decision.

Answer 2

If you look at fedora , then there is a clear transition to systemd. Everything runs through it.
Directory with all this: /etc/systemd/system
There are two main modes:
multi-user.target is like runlevel 3
graphical.target is runlevel 5
They are also designed as directories in /etc/systemd/system with links to scripts that should be run at system startup.
The mode itself is prescribed to mine in the file: default.target
The graphical manager is used by gdm. It usually starts like this:
The status can be viewed like this:
systemctl status gdm