Boot black screen with a message

Hello, i just upgraded from Ubuntu 15.10 to 16.04.
Everything was alright until i got a 100% usage of cpu i searched and i found that noveau drivers maybe was causing this, so i changed to proprietary drivers.
Now i can't boot into my desktop, if i boot in the normal way after the purple screen saying "Ubuntu" i get this message: "/dev/sda8: clean, 241391/4235264 files, 7230305/16920576 blocks" in a black screen.
Then i tried to boot with recovery mode, this way i can reach the login screen but i can't login, i write my password and then i retu to the login screen again. How can i solve this?