"init 5" would start your graphical environment if you just executed "startx" then it would run your /.xinitrc file and may just give you an X login prompt!

I alway do init 5 or possibly telinit 5 depending on which disto I'm using!

If it boots up in init 3 (prompt) then you can edit your /etc/inittab and change the init setting to 5. If it fails when changing to init 5 (I often get this when I update my Nvidia driver) then edit your /etc/X11/XFree86Config to the correct graphics driver.

This is the page I follow for my Nvidia card which may help...
http://download.nvidia.com/XFree86/L...ection-02.html