1.cvt w h fps
2.xrandr --newmode "mode_name" <output of 1>
3.xrandr --andmode VGA(which show in the list of command xrandr)"mode name you new in step 2"
4.xrandr --output --mode VGA "mode_name"
强行设置分辨率
原文：http://www.cnblogs.com/tsingyixy/p/3536485.html
