There may be an installation/configuration. I'm not sufficiently knowledgable to be able to tell you where to look for the solution.
The only time I've had such a problem, it was a matter of too little partiton space: in particular, the partition in which /tmp is located.
When you log in to GUI mode, tmp files are created for the desktop. If the partition is too small, you can't create the tmp files, and you are dropped to text mode. The solution is to do some house cleaning: clear out browser caches, tmp files in /tmp, etc. Also, it there is room to do so, resize the partition to make it larger.