新增解析度

版本：Ubuntu 16.04

1.取得相關參數
$ cvt 1366 768
# 1368x768 59.88 Hz (CVT) hsync: 47.79 kHz; pclk: 85.25 MHz
Modeline "1368x768_60.00"   85.25  1368 1440 1576 1784  768 771 781 798 -hsync +vsync
$ xrandr
Screen 0: minimum 320 x 200, current 1368 x 768, maximum 16384 x 16384
HDMI-0 disconnected (normal left inverted right x axis y axis)
DVI-0 disconnected (normal left inverted right x axis y axis)
VGA-0 connected primary 1368x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1024x768      60.00 
   800x600       60.32    56.25 
   848x480       60.00 
   640x480       59.94 
   1920x1080     59.96 
   1440x900      59.89 
   1368x768      59.88*

2.設定
$ sudo xrandr --newmode "1368x768"   85.25  1368 1440 1576 1784  768 771 781 798 -hsync +vsync
$ sudo xrandr --addmode VGA-0 "1368x768"