我的目标是设置一个多头环境：我需要在两个屏幕上都提供扩展桌面，并能够将窗口从一个屏幕拖放到另一个屏幕。左侧屏幕在VGA端口上，右侧屏幕插入HDMI端口。
我尝试了一下，xorg.conf但似乎无法设置正确的配置以使多头工作。
这是我的xorg.conf：
Section "ServerLayout"
Identifier "X.org Configured"
Screen 0 "Screen0" 0 0
InputDevice "Mouse0" "CorePointer"
InputDevice "Keyboard0" "CoreKeyboard"
EndSection
Section "Files"
ModulePath "/usr/local/lib/xorg/modules"
FontPath "/usr/local/lib/X11/fonts/misc/"
FontPath "/usr/local/lib/X11/fonts/TTF/"
FontPath "/usr/local/lib/X11/fonts/OTF"
FontPath "/usr/local/lib/X11/fonts/Type1/"
FontPath "/usr/local/lib/X11/fonts/100dpi/"
FontPath "/usr/local/lib/X11/fonts/75dpi/"
EndSection
Section "Module"
Load "dbe"
Load "dri"
Load "dri2"
Load "extmod"
Load "record"
Load "glx"
EndSection
Section "InputDevice"
Identifier "Keyboard0"
Driver "evdev"
Option "XkbLayout" "fr"
#Option "XkbModel" "pc105"
#Option "Device" "/dev/ukbd0"
#Option "CoreKeyboard"
EndSection
Section "InputDevice"
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/sysmouse"
Option "ZAxisMapping" "4 5 6 7"
EndSection
Section "Monitor"
Identifier "Monitor0"
VendorName "Monitor Vendor"
ModelName "Monitor Model"
EndSection
Section "Device"
### Available Driver options are:-
### Values: <i>: integer, <f>: float, <bool>: "True"/"False",
### <string>: "String", <freq>: "<f> Hz/kHz/MHz"
### [arg]: arg optional
#Option "ShadowFB" # [<bool>]
#Option "DefaultRefresh" # [<bool>]
#Option "ModeSetClearScreen" # [<bool>]
Identifier "Card0"
Driver "vesa"
VendorName "Intel Corporation"
BoardName "Xeon E3-1200 v2/3rd Gen Core processor Graphics Controller"
BusID "PCI:0:2:0"
EndSection
Section "Screen"
Identifier "Screen0"
Device "Card0"
Monitor "Monitor0"
SubSection "Display"
Viewport 0 0
Depth 1
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 4
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 8
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 15
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 16
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 24
EndSubSection
EndSection
我读了某处我需要设置Virtual和Modes指令，因此我修改了配置如下：
Section "Screen"
# ...
SubSection "Display"
Viewport 0 0
Depth 24
Virtual 3600 1080
Modes "1920x1080" "1680x1050"
EndSubSection
EndSection
结果是主屏幕上的图像模糊不清。虽然我可以移动鼠标，但看到桌面实际上已经扩展。但它无法使用，并且仅在一个屏幕上运行。
我也已XRandr按照安装本文档但输出$ xrandr -q如下：
xrandr: Failed to get size of gamma for output default
Screen 0: minimum 640 x 480, current 1920 x 1200, maximum 1920 x 1200
default connected 1920x1200+0+0 0mm x 0mm
1920x1200 0.00*
1600x1200 0.00
1280x1024 0.00
1024x768 0.00
800x600 0.00
640x480 0.00
所以我看到只检测到一个屏幕，因此我无法运行以下命令来按照我的意愿显示两个屏幕：
$ xrandr --output <RightScreen> --right-of default
因为我不知道 的名字<RightScreen>。
最奇怪的是，在HDMI插入右侧屏幕的情况下重新启动时，启动信息出现在右侧屏幕上，而主（左侧）屏幕上什么都没有出现。当我登录时，XFCE 无法在右侧屏幕上显示任何内容，导致两个屏幕都无法使用。唯一的解决方案是手动关闭计算机（按下按钮），拔下右侧屏幕并再次启动。
我遗漏了什么？我对 Linux 世界还很陌生，FreeBSD如果我做错了什么，请多多包涵。
任何帮助都将不胜感激。谢谢！