How to kill a Frozen X server in Linux

IIf your X window freezes there are two ways to kill X server. The first one is simple hit
Ctrl+Alt+Backspace. The second one is more complicated. Hit Ctrl+Alt+F2 to open a new virtual console. Login with your username and password. Then run # ps -ax | grep startx
This gives the PID of the X server. Then kill the server using the command kill -9 PID_Number
Now use Alt+F1 to go back to your previous console.