我有一个双显示器 Linux 系统。过去，我有一个质量差很多的无名显卡，能够让它工作。但是，当我切换到 AMD Radeon 时，它（Linux/驱动程序/Mesa？）无法识别我的第二台显示器。尽管支持 4 个插头，但该卡似乎只能用于一台显示器。我想运行 lxrandr 并告诉它将 2 个显示器变成 1 个大宽显示器（有效）。请注意，我知道如何做到这一点（如果只有驱动程序/linux/？）会起作用。
我的卡有 4 个插头（2 个 HDMI 和 2 个 Display）。两个显示器都是 Display。我尝试过切换显示器电缆和显示器。如果我将电缆从卡连接到正在工作的显示器，然后将显示器换成另一个，另一个仍然正常工作。这不是显示器的问题，也不是显示端口电缆的问题。我想运行 lxrandr 并为第二台显示器设置显示器/显示器，但它只显示一个。
以下是我用来收集有关我的系统信息的命令。
$ uname -a
$ lspci |grep VGA
0c:00.0 VGA compatible controller: Advanced Micro Devices, Inc. \[AMD/ATI\] Navi 23 \[Radeon RX 6600/6600 XT/6600M\] (rev c1)
（我运行这个强烈暗示显卡正在被使用）
$ glxgears
17627 frames in 5.0 seconds = 3523.677 FPS
X connection to :0 broken (explicit kill or server shutdown).
$ xrandr --listmonitors
xrandr: Failed to get size of gamma for output default
Monitors: 1
0: +\*default 1920/508x1080/286+0+0 default
$ xrandr --listproviders
Providers: number : 0
我尝试按照如下所示安装设置，但没有帮助。
$ sudo apt list --installed |grep amdgpu
WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
amdgpu-core/unknown,now 20.45-1188099 all \[installed,automatic\]
amdgpu-dkms-firmware/unknown,now 1:5.6.20.906316-1188099 all \[installed,automatic\]
amdgpu-dkms/unknown,now 1:5.6.20.906316-1188099 all \[installed\]
amdgpu-install/focal,focal,now 22.20.50200-1438746\~20.04 all \[installed\]
amdgpu-lib32/unknown,now 20.45-1188099 amd64 \[installed\]
amdgpu-lib/unknown,now 20.45-1188099 amd64 \[installed\]
amdgpu-pin/unknown,now 20.45-1188099 all \[installed\]
amdgpu/unknown,now 20.45-1188099 amd64 \[installed\]
gst-omx-amdgpu/unknown,now 1.0.0.1-1188099 amd64 \[installed,automatic\]
libdrm-amdgpu-amdgpu1/unknown,now 1:2.4.100-1188099 amd64 \[installed,automatic\]
libdrm-amdgpu-amdgpu1/unknown,now 1:2.4.100-1188099 i386 \[installed,automatic\]
libdrm-amdgpu-common/unknown,now 1.0.0-1188099 all \[installed,automatic\]
libdrm-amdgpu-radeon1/unknown,now 1:2.4.100-1188099 amd64 \[installed,automatic\]
libdrm-amdgpu-radeon1/unknown,now 1:2.4.100-1188099 i386 \[installed,automatic\]
libdrm-amdgpu1/focal-updates,focal-security,now 2.4.107-8ubuntu1\~20.04.2 amd64 \[installed\]
libdrm-amdgpu1/focal-updates,focal-security,now 2.4.107-8ubuntu1\~20.04.2 i386 \[installed,automatic\]
libdrm2-amdgpu/unknown,now 1:2.4.100-1188099 amd64 \[installed,automatic\]
libdrm2-amdgpu/unknown,now 1:2.4.100-1188099 i386 \[installed,automatic\]
libegl1-amdgpu-mesa-drivers/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libegl1-amdgpu-mesa-drivers/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libegl1-amdgpu-mesa/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libegl1-amdgpu-mesa/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libgbm1-amdgpu/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libgbm1-amdgpu/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libgl1-amdgpu-mesa-dri/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libgl1-amdgpu-mesa-dri/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libgl1-amdgpu-mesa-glx/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libgl1-amdgpu-mesa-glx/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libglapi-amdgpu-mesa/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libglapi-amdgpu-mesa/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libgles1-amdgpu-mesa/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libgles1-amdgpu-mesa/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libgles2-amdgpu-mesa/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libgles2-amdgpu-mesa/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libllvm10.0-amdgpu/unknown,now 1:10.0-1188099 amd64 \[installed,automatic\]
libllvm10.0-amdgpu/unknown,now 1:10.0-1188099 i386 \[installed,automatic\]
libosmesa6-amdgpu/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libosmesa6-amdgpu/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libxatracker2-amdgpu/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libxatracker2-amdgpu/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
mesa-amdgpu-omx-drivers/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
mesa-amdgpu-va-drivers/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
mesa-amdgpu-va-drivers/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
mesa-amdgpu-vdpau-drivers/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
mesa-amdgpu-vdpau-drivers/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
xserver-xorg-amdgpu-video-amdgpu/unknown,now 1:19.1.0-1188099 amd64 \[installed,automatic\]
xserver-xorg-video-amdgpu/focal,now 19.1.0-1 amd64 \[installed\]
WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
amdgpu-core/unknown,now 20.45-1188099 all \[installed,automatic\]
amdgpu-dkms-firmware/unknown,now 1:5.6.20.906316-1188099 all \[installed,automatic\]
amdgpu-dkms/unknown,now 1:5.6.20.906316-1188099 all \[installed\]
amdgpu-install/focal,focal,now 22.20.50200-1438746\~20.04 all \[installed\]
amdgpu-lib32/unknown,now 20.45-1188099 amd64 \[installed\]
amdgpu-lib/unknown,now 20.45-1188099 amd64 \[installed\]
amdgpu-pin/unknown,now 20.45-1188099 all \[installed\]
amdgpu/unknown,now 20.45-1188099 amd64 \[installed\]
gst-omx-amdgpu/unknown,now 1.0.0.1-1188099 amd64 \[installed,automatic\]
libdrm-amdgpu-amdgpu1/unknown,now 1:2.4.100-1188099 amd64 \[installed,automatic\]
libdrm-amdgpu-amdgpu1/unknown,now 1:2.4.100-1188099 i386 \[installed,automatic\]
libdrm-amdgpu-common/unknown,now 1.0.0-1188099 all \[installed,automatic\]
libdrm-amdgpu-radeon1/unknown,now 1:2.4.100-1188099 amd64 \[installed,automatic\]
libdrm-amdgpu-radeon1/unknown,now 1:2.4.100-1188099 i386 \[installed,automatic\]
libdrm-amdgpu1/focal-updates,focal-security,now 2.4.107-8ubuntu1\~20.04.2 amd64 \[installed\]
libdrm-amdgpu1/focal-updates,focal-security,now 2.4.107-8ubuntu1\~20.04.2 i386 \[installed,automatic\]
libdrm2-amdgpu/unknown,now 1:2.4.100-1188099 amd64 \[installed,automatic\]
libdrm2-amdgpu/unknown,now 1:2.4.100-1188099 i386 \[installed,automatic\]
libegl1-amdgpu-mesa-drivers/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libegl1-amdgpu-mesa-drivers/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libegl1-amdgpu-mesa/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libegl1-amdgpu-mesa/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libgbm1-amdgpu/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libgbm1-amdgpu/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libgl1-amdgpu-mesa-dri/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libgl1-amdgpu-mesa-dri/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libgl1-amdgpu-mesa-glx/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libgl1-amdgpu-mesa-glx/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libglapi-amdgpu-mesa/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libglapi-amdgpu-mesa/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libgles1-amdgpu-mesa/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libgles1-amdgpu-mesa/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libgles2-amdgpu-mesa/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libgles2-amdgpu-mesa/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libllvm10.0-amdgpu/unknown,now 1:10.0-1188099 amd64 \[installed,automatic\]
libllvm10.0-amdgpu/unknown,now 1:10.0-1188099 i386 \[installed,automatic\]
libosmesa6-amdgpu/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libosmesa6-amdgpu/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
libxatracker2-amdgpu/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
libxatracker2-amdgpu/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
mesa-amdgpu-omx-drivers/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
mesa-amdgpu-va-drivers/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
mesa-amdgpu-va-drivers/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
mesa-amdgpu-vdpau-drivers/unknown,now 1:20.1.6-1188099 amd64 \[installed,automatic\]
mesa-amdgpu-vdpau-drivers/unknown,now 1:20.1.6-1188099 i386 \[installed,automatic\]
xserver-xorg-amdgpu-video-amdgpu/unknown,now 1:19.1.0-1188099 amd64 \[installed,automatic\]
xserver-xorg-video-amdgpu/focal,now 19.1.0-1 amd64 \[installed\]
$ glxinfo | egrep -i 'Direct|String'
direct rendering: Yes
server glx vendor string: SGI
server glx version string: 1.4
client glx vendor string: Mesa Project and SGI
client glx version string: 1.4
OpenGL vendor string: VMware, Inc.
OpenGL renderer string: llvmpipe (LLVM 10.0.1, 256 bits)
OpenGL core profile version string: 3.3 (Core Profile) Mesa 20.1.6
OpenGL core profile shading language version string: 3.30
GL\_AMD\_gpu\_shader\_int64, GL\_AMD\_multi\_draw\_indirect,
GL\_ARB\_derivative\_control, GL\_ARB\_direct\_state\_access,
GL\_ARB\_draw\_elements\_base\_vertex, GL\_ARB\_draw\_indirect,
GL\_ARB\_half\_float\_vertex, GL\_ARB\_indirect\_parameters,
GL\_ARB\_multi\_draw\_indirect, GL\_ARB\_occlusion\_query2,
OpenGL version string: 3.1 Mesa 20.1.6
OpenGL shading language version string: 1.40
GL\_AMD\_multi\_draw\_indirect, GL\_AMD\_query\_buffer\_object,
GL\_ARB\_direct\_state\_access, GL\_ARB\_draw\_buffers,
GL\_ARB\_draw\_indirect, GL\_ARB\_draw\_instanced, GL\_ARB\_enhanced\_layouts,
GL\_ARB\_indirect\_parameters, GL\_ARB\_instanced\_arrays,
GL\_ARB\_map\_buffer\_range, GL\_ARB\_multi\_bind, GL\_ARB\_multi\_draw\_indirect,
GL\_EXT\_direct\_state\_access, GL\_EXT\_draw\_buffers2, GL\_EXT\_draw\_instanced,
OpenGL ES profile version string: OpenGL ES 3.1 Mesa 20.1.6
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.10