You should try to reinstall. Although in my case it really didn't help as I kept getting the same blank screen after login.did you try to reconfigure xserver? If you do the key combo of "ctrl + f2" of any of the function keys it will bring you to a terminal. You can do that as soon as u get the blank screen. make sure to type dpkg-reconfigure xserver-xorg in terminal. That will start to reconfigure xserver, just answer the questions and keep your fingers crossed. For some people that has worked, others like myself nothing...