I just installed ubuntu 13.10(amd64) in my HP Pavilion 15-e044TX with AMD HD8670M Graphic card. after the first boot, error message was displayed "the system is running in low-graphics mode".

so I entered to shell pressing Ctrl + Alt + F1, and then I entered this command below to solve this problem:

sudo apt-get install fglrx

after reboot, login screen was displayed correctly, but after Log in to my user, displayed just a black screen and cursor.

I tried to find a solution much time, but there is no answer to solve my problems.