超宽显示器仅部分屏幕显示桌面

Question

我目前在 MSI Dominator 笔记本电脑上运行 Ubuntu 16.04 LTS，笔记本电脑屏幕已禁用，仅使用外接显示器（LG 34UC88 @ 3440x1440 21:9），Ubuntu 拒绝在整个显示器高度上显示。它显示在显示器的整个宽度（3440 像素）上，但仅显示在显示器的顶部 1080 像素上，导致以下情况：

我的笔记本电脑上有一块 Nvidia GTX870M 和 Intel 集成显卡，以及来自 nvidia-361 repo 的 NVIDIA 二进制驱动程序版本 361.42。

这是我的xrandr -q输出：

Screen 0: minimum 8 x 8, current 3440 x 1440, maximum 16384 x 16384
HDMI-0 disconnected (normal left inverted right x axis y axis)
DP-0 disconnected (normal left inverted right x axis y axis)
DP-1 connected primary 3440x1440+0+0 (normal left inverted right x axis y axis) 800mm x 335mm
   3440x1440     59.97*+  49.99    29.99  
   2560x1080     60.00    59.94    50.00  
   1920x1080     60.00    59.94    50.00  
   1680x1050     59.95  
   1600x900      60.00  
   1280x1024     60.02  
   1280x800      59.81  
   1280x720      60.00    59.94    50.00  
   1152x864      59.96  
   1024x768      60.00  
   800x600       60.32  
   720x576       50.00  
   720x480       59.94  
   640x480       59.94    59.93  
eDP-1 connected
   1920x1080     60.02 +  59.93  
   1680x1050     59.95    59.88  
   1600x1024     60.17  
   1400x1050     59.98  
   1280x1024     60.02  
   1440x900      59.89  
   1280x960      60.00  
   1360x768      59.80    59.96  
   1152x864      60.00  
   1024x768      60.04    60.00  
   960x720       60.00  
   928x696       60.05  
   896x672       60.01  
   960x600       60.00  
   960x540       59.99  
   800x600       60.00    60.32    56.25  
   840x525       60.01    59.88  
   800x512       60.17  
   700x525       59.98  
   640x512       60.02  
   720x450       59.89  
   640x480       60.00    59.94  
   680x384       59.80    59.96  
   576x432       60.06  
   512x384       60.00  
   400x300       60.32    56.34  
   320x240       60.05  
VGA-1 disconnected
  1680x1050 (0x47) 146.250MHz -HSync +VSync
        h: width  1680 start 1784 end 1960 total 2240 skew    0 clock  65.29KHz
        v: height 1050 start 1053 end 1059 total 1089           clock  59.95Hz
  1280x1024 (0x4b) 108.000MHz +HSync +VSync
        h: width  1280 start 1328 end 1440 total 1688 skew    0 clock  63.98KHz
        v: height 1024 start 1025 end 1028 total 1066           clock  60.02Hz
  1024x768 (0x52) 65.000MHz -HSync -VSync
        h: width  1024 start 1048 end 1184 total 1344 skew    0 clock  48.36KHz
        v: height  768 start  771 end  777 total  806           clock  60.00Hz
  800x600 (0x59) 40.000MHz +HSync +VSync
        h: width   800 start  840 end  968 total 1056 skew    0 clock  37.88KHz
        v: height  600 start  601 end  605 total  628           clock  60.32Hz
  640x480 (0x62) 25.175MHz -HSync -VSync
        h: width   640 start  656 end  752 total  800 skew    0 clock  31.47KHz
        v: height  480 start  490 end  492 total  525           clock  59.94Hz

以下是我当前的xorg.conf设置：

Section "ServerLayout"
    Identifier "layout"
    Screen 0 "nvidia"
    Inactive "intel"
EndSection

Section "Device"
    Identifier "intel"
    Driver "modesetting"
    BusID "PCI:0@0:2:0"
    Option "AccelMethod" "None"
EndSection

Section "Screen"
    Identifier "intel"
    Device "intel"
EndSection

Section "Device"
    Identifier "nvidia"
    Driver "nvidia"
    BusID "PCI:1@0:0:0"
    Option "ConstrainCursor" "off"
EndSection

Section "Screen"
    Identifier "nvidia"
    Device "nvidia"
    Option "AllowEmptyInitialConfiguration" "on"
    Option "IgnoreDisplayDevices" "CRT"
EndSection

任何帮助都将不胜感激。我的下一步是让它在双屏设置下与内置笔记本电脑屏幕一起正确显示，如果你对此也有任何想法的话。