Comment 8 for bug 20006

I actually looked at the xorg.conf file myself a little more and fixed my
problem. All I did was replace the horizontal sync with 30.0-121.0 and the
vertical sync with 50.0-160.0 and upon restart Ubuntu automatically selected 85
Hz as default. All is well now, on my desktop.

Though I wouldn't expect most people new to Linux to know their
horizontal/vertical sync ranges and then modify their xorg.conf file in the
right place to fix the system.