ubuntu双屏调整分辨率

查看屏幕硬件指标

# xrandr
Screen 0: minimum 8 x 8, current 2390 x 768, maximum 32767 x 32767
LVDS1 connected primary 1366x768+0+0 (normal left inverted right x axis y axis) 277mm x 156mm
   1366x768       60.1*+
   1360x768       59.8     60.0  
   1024x768       60.0  
   800x600        60.3     56.2  
   640x480        59.9  
DP1 disconnected (normal left inverted right x axis y axis)
DP2 disconnected (normal left inverted right x axis y axis)
DP3 disconnected (normal left inverted right x axis y axis)
HDMI1 disconnected (normal left inverted right x axis y axis)
HDMI2 disconnected (normal left inverted right x axis y axis)
HDMI3 disconnected (normal left inverted right x axis y axis)
VGA1 connected 1024x768+1366+0 (normal left inverted right x axis y axis) 408mm x 255mm
   1440x900       59.9 +   75.0  
   1280x1024      75.0     60.0  
   1280x960       60.0  
   1152x864       75.0  
   1024x768       75.1     70.1     60.0* 
   832x624        74.6  
   800x600        72.2     75.0     60.3     56.2  
   640x480        75.0     72.8     66.7     60.0  
   720x400        70.1  
VIRTUAL1 disconnected (normal left inverted right x axis y axis)
  1440x900_60.00 (0x1b4)  106.5MHz
        h: width  1440 start 1528 end 1672 total 1904 skew    0 clock   55.9KHz
        v: height  900 start  903 end  909 total  934           clock   59.9Hz

# VGA1是外接显示器的硬件指标，可以看出最佳分辨率是1440x900

生成modeline

# cvt 1440 900
# 1440x900 59.89 Hz (CVT 1.30MA) hsync: 55.93 kHz; pclk: 106.50 MHz
Modeline "1440x900_60.00"  106.50  1440 1528 1672 1904  900 903 909 934 -hsync +vsync

创建modeline

xrandr --newmode "1440x900_60.00"  106.50  1440 1528 1672 1904  900 903 909 934 -hsync +vsync

VGA1添加modeline

xrandr --addmode VGA1 "1440x900_60.00"

应用

xrandr --output VGA1 --mode "1440x900_60.00"