通常，屏幕突然熄灭意味着背光已损坏。 但这里的情况并非如此。 这是一台双启动机器，在 POST、GRUB 和 Windows 10 期间，内部屏幕都完好无损。所以这不是背光的问题，而且我很确定这与硬件无关。
这是一台配备两块显卡的戴尔 M6800：一块低功耗英特尔显卡和一块 Quadro K5100M。NVIDIA X 服务器设置 GUI 报告单个屏幕（外部屏幕）以 1920x1080x60Hz 运行，就像 LXQt 的显示器设置一样。少数应用程序似乎足够清晰 - 例如 NVIDIA X 服务器和 Firefox，这就是我写这篇文章的方式 - 但大多数东西的文本只有几个模糊的像素高，包括终端。如果我没有看错的话，LXQt 的外观配置仍然将字体大小设置为 11pt，DPI 设置为 96。
我大约一小时前刚刚更新 - sudo apt [update|full-upgrade|autoremove] - 得到了一些，然后重新启动，没有任何变化。
知道是什么原因造成的吗？如何让内部屏幕恢复正常并显示合适的系统字体？
根据聊天记录整理：
/var/log/Xorg.0.log是：
https://pastebin.ubuntu.com/p/24tSjCHdmW/
aaron@aaron-Lubuntu:~$ xrandr --listmonitors
Monitors: 1
0: +DP-0 1920/1150x1080/650+0+0 DP-0
aaron@aaron-Lubuntu:~$ xrandr --listproviders
Providers: number : 1
Provider 0: id: 0x2d8 cap: 0x1, Source Output crtcs: 4 outputs: 8 associated providers: 0 name:NVIDIA-0
aaron@aaron-Lubuntu:~$
aaron@aaron-Lubuntu:~$ glxinfo | grep OpenGL
Command 'glxinfo' not found, but can be installed with:
sudo apt install mesa-utils
aaron@aaron-Lubuntu:~$ sudo apt install mesa-utils
[sudo] password for aaron:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
mesa-utils
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 34.2 kB of archives.
After this operation, 150 kB of additional disk space will be used.
Get:1 http://us.archive.ubuntu.com/ubuntu focal/universe amd64 mesa-utils amd64 8.4.0-1build1 [34.2 kB]
Fetched 34.2 kB in 1s (40.3 kB/s)
Selecting previously unselected package mesa-utils.
(Reading database ... 296803 files and directories currently installed.)
Preparing to unpack .../mesa-utils_8.4.0-1build1_amd64.deb ...
Unpacking mesa-utils (8.4.0-1build1) ...
Setting up mesa-utils (8.4.0-1build1) ...
Processing triggers for man-db (2.9.1-1) ...
aaron@aaron-Lubuntu:~$ glxinfo | grep OpenGL
OpenGL vendor string: NVIDIA Corporation
OpenGL renderer string: Quadro K5100M/PCIe/SSE2
OpenGL core profile version string: 4.6.0 NVIDIA 470.103.01
OpenGL core profile shading language version string: 4.60 NVIDIA
OpenGL core profile context flags: (none)
OpenGL core profile profile mask: core profile
OpenGL core profile extensions:
OpenGL version string: 4.6.0 NVIDIA 470.103.01
OpenGL shading language version string: 4.60 NVIDIA
OpenGL context flags: (none)
OpenGL profile mask: (none)
OpenGL extensions:
OpenGL ES profile version string: OpenGL ES 3.2 NVIDIA 470.103.01
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.20
OpenGL ES profile extensions:
aaron@aaron-Lubuntu:~$ sudo apt install nvidia-prime
Reading package lists... Done
Building dependency tree
Reading state information... Done
nvidia-prime is already the newest version (0.8.16~0.20.04.1).
nvidia-prime set to manually installed.
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
aaron@aaron-Lubuntu:~$
aaron@aaron-Lubuntu:~$ cat ./.bash_history | grep nvidia
sudo apt install nvidia-driver-430
aaron@aaron-Lubuntu:~$
aaron@aaron-Lubuntu:~$ lspci
00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor DRAM Controller (rev 06)
00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor PCI Express x16 Controller (rev 06)
00:14.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB xHCI (rev 04)
00:16.0 Communication controller: Intel Corporation 8 Series/C220 Series Chipset Family MEI Controller #1 (rev 04)
00:19.0 Ethernet controller: Intel Corporation Ethernet Connection I217-LM (rev 04)
00:1a.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #2 (rev 04)
00:1b.0 Audio device: Intel Corporation 8 Series/C220 Series Chipset High Definition Audio Controller (rev 04)
00:1c.0 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #1 (rev d4)
00:1c.2 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #3 (rev d4)
00:1c.3 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #4 (rev d4)
00:1c.4 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #5 (rev d4)
00:1c.6 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #7 (rev d4)
00:1c.7 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #8 (rev d4)
00:1d.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #1 (rev 04)
00:1f.0 ISA bridge: Intel Corporation QM87 Express LPC Controller (rev 04)
00:1f.2 RAID bus controller: Intel Corporation 82801 Mobile SATA Controller [RAID mode] (rev 04)
00:1f.3 SMBus: Intel Corporation 8 Series/C220 Series Chipset Family SMBus Controller (rev 04)
01:00.0 VGA compatible controller: NVIDIA Corporation GK104GLM [Quadro K5100M] (rev a1)
01:00.1 Audio device: NVIDIA Corporation GK104 HDMI Audio Controller (rev a1)
03:00.0 Network controller: Intel Corporation Wireless 7260 (rev bb)
11:00.0 SD Host controller: O2 Micro, Inc. SD/MMC Card Reader Controller (rev 01)
aaron@aaron-Lubuntu:~$ lshw -C video
WARNING: you should run this program as super-user.
*-display
description: VGA compatible controller
product: GK104GLM [Quadro K5100M]
vendor: NVIDIA Corporation
physical id: 0
bus info: pci@0000:01:00.0
version: a1
width: 64 bits
clock: 33MHz
capabilities: vga_controller bus_master cap_list rom
configuration: driver=nvidia latency=0
resources: irq:39 memory:f4000000-f4ffffff memory:e0000000-efffffff memory:f0000000-f1ffffff ioport:e000(size=128) memory:c0000-dffff
WARNING: output may be incomplete or inaccurate, you should run this program as super-user.
aaron@aaron-Lubuntu:~$ sudo lshw -C video
[sudo] password for aaron:
*-display
description: VGA compatible controller
product: GK104GLM [Quadro K5100M]
vendor: NVIDIA Corporation
physical id: 0
bus info: pci@0000:01:00.0
version: a1
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress vga_controller bus_master cap_list rom
configuration: driver=nvidia latency=0
resources: irq:39 memory:f4000000-f4ffffff memory:e0000000-efffffff memory:f0000000-f1ffffff ioport:e000(size=128) memory:c0000-dffff
aaron@aaron-Lubuntu:~$ apt policy xserver-xorg-video-intel
xserver-xorg-video-intel:
Installed: 2:2.99.917+git20200226-1
Candidate: 2:2.99.917+git20200226-1
Version table:
*** 2:2.99.917+git20200226-1 500
500 http://us.archive.ubuntu.com/ubuntu focal/main amd64 Packages
100 /var/lib/dpkg/status
aaron@aaron-Lubuntu:~$
aaron@aaron-Lubuntu:~$ dpkg -l | grep mesa
ii libegl-mesa0:amd64 21.2.6-0ubuntu0.1~20.04.2 amd64 free implementation of the EGL API -- Mesa vendor library
ii libgl1-mesa-dri:amd64 21.2.6-0ubuntu0.1~20.04.2 amd64 free implementation of the OpenGL API -- DRI modules
ii libgl1-mesa-dri:i386 21.2.6-0ubuntu0.1~20.04.2 i386 free implementation of the OpenGL API -- DRI modules
ii libglapi-mesa:amd64 21.2.6-0ubuntu0.1~20.04.2 amd64 free implementation of the GL API -- shared library
ii libglapi-mesa:i386 21.2.6-0ubuntu0.1~20.04.2 i386 free implementation of the GL API -- shared library
ii libglu1-mesa:amd64 9.0.1-1build1 amd64 Mesa OpenGL utility library (GLU)
ii libglx-mesa0:amd64 21.2.6-0ubuntu0.1~20.04.2 amd64 free implementation of the OpenGL API -- GLX vendor library
ii libglx-mesa0:i386 21.2.6-0ubuntu0.1~20.04.2 i386 free implementation of the OpenGL API -- GLX vendor library
ii mesa-utils 8.4.0-1build1 amd64 Miscellaneous Mesa GL utilities
ii mesa-va-drivers:amd64 21.2.6-0ubuntu0.1~20.04.2 amd64 Mesa VA-API video acceleration drivers
ii mesa-vdpau-drivers:amd64 21.2.6-0ubuntu0.1~20.04.2 amd64 Mesa VDPAU video acceleration drivers
ii mesa-vulkan-drivers:amd64 21.2.6-0ubuntu0.1~20.04.2 amd64 Mesa Vulkan graphics drivers
ii mesa-vulkan-drivers:i386 21.2.6-0ubuntu0.1~20.04.2 i386 Mesa Vulkan graphics drivers
aaron@aaron-Lubuntu:~$ prime-select query
nvidia
aaron@aaron-Lubuntu:~$
为了进行比较，实时 USB 具有以下内容/var/log/Xorg.0.log：
https://pastebin.ubuntu.com/p/GDDhPjFTCv/
和：
lubuntu@lubuntu:~$ xrandr --listmonitors
Monitors: 2
0: +eDP-1 1920/382x1080/215+0+0 eDP-1
1: +DP-3 1920/708x1080/398+1920+0 DP-3
lubuntu@lubuntu:~$ xrandr --listproviders
Providers: number : 1
Provider 0: id: 0x48 cap: 0x9, Source Output, Sink Offload crtcs: 4 outputs: 5 associated providers: 0 name:modesetting
lubuntu@lubuntu:~$