For some weird reason, probably related to some of the default settings of video acceleration (I now have an nVidia), playing DivX5 videos caused a green vertical bar to show up. This happened with all the players. I don’t know where the definitive solution lies, but for VLC I found the solution in this thread:
Go to the preferences menu in VLC and go to the video options, in the output i just played with the settings and X11 works for me.
This exact thing worked for me.