我有一台双启动的 Dell Inspiron 17-7700，配备 Nvidia GeForce 940MX。我打算买一台 4k 显示器，但我想测试它是否真的可以在我的笔记本电脑上使用。我尝试连接的显示器是 AOC U2790PQU。
在 Windows 上一切正常。切换到 Ubuntu 时，我无法选择 4k 分辨率。
xrandr
仅显示最高 1920x1080。创建自定义配置文件不起作用：
xrandr --output HDMI-1 --mode "Mode 0" --verbose
screen 0: 3840x2160 1013x570 mm 96.25dpi
crtc 1: Mode 0 60.00 +0+0 "HDMI-1"
xrandr: Configure crtc 1 failed
crtc 0: disable
crtc 1: disable
crtc 2: disable
screen 0: revert
crtc 0: revert
crtc 1: revert
crtc 2: revert
我尝试使用 Ubuntu Live USB 来查看是否是我的安装问题（我弄乱了很多，我想也许是 i3 出了问题）。这也不起作用。
我已采取更改 x.org 文件并添加 modlines 的方法这里 (Linux 上 4k@60hz)。这将输出与上面相同的错误（配置 crtc 1 失败）。
将图形驱动程序（在软件中心 - 附加驱动程序）从 Nouveau 更改为 NVIDIA 驱动程序元包 nvidia-driver-435（专有，已测试）没有帮助。
相关信息（我当然不确定这是否是全部，如果缺少什么请告诉我）：
sudo lshw -C video
*-display
description: VGA compatible controller
product: HD Graphics 620
vendor: Intel Corporation
physical id: 2
bus info: pci@0000:00:02.0
version: 02
width: 64 bits
clock: 33MHz
capabilities: pciexpress msi pm vga_controller bus_master cap_list rom
configuration: driver=i915 latency=0
resources: irq:145 memory:d4000000-d4ffffff memory:b0000000-bfffffff ioport:f000(size=64) memory:c0000-dffff
*-display UNCLAIMED
description: 3D controller
product: GM108M [GeForce 940MX]
vendor: NVIDIA Corporation
physical id: 0
bus info: pci@0000:01:00.0
version: a2
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress bus_master cap_list
configuration: latency=0
resources: memory:d2000000-d2ffffff memory:c0000000-cfffffff memory:d0000000-d1ffffff ioport:e000(size=128) memory:d3000000-d307ffff
-
xrandr
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 16384
eDP-1 connected primary 1920x1080+0+0 (normal left inverted rig
1920x1080 60.00*+ 59.97 59.96 59.93 48.07
1680x1050 59.95 59.88
1600x1024 60.17
1400x1050 59.98
1600x900 59.99 59.94 59.95 59.82
1280x1024 60.02
1440x900 59.89
1400x900 59.96 59.88
1280x960 60.00
1440x810 60.00 59.97
1368x768 59.88 59.85
1360x768 59.80 59.96
1280x800 59.99 59.97 59.81 59.91
1152x864 60.00
1280x720 60.00 59.99 59.86 59.74
1024x768 60.04 60.00
960x720 60.00
928x696 60.05
896x672 60.01
1024x576 59.95 59.96 59.90 59.82
960x600 59.93 60.00
960x540 59.96 59.99 59.63 59.82
800x600 60.00 60.32 56.25
840x525 60.01 59.88
864x486 59.92 59.57
800x512 60.17
700x525 59.98
800x450 59.95 59.82
640x512 60.02
720x450 59.89
700x450 59.96 59.88
640x480 60.00 59.94
720x405 59.51 58.99
684x384 59.88 59.85
680x384 59.80 59.96
640x400 59.88 59.98
576x432 60.06
640x360 59.86 59.83 59.84 59.32
512x384 60.00
512x288 60.00 59.92
480x270 59.63 59.82
400x300 60.32 56.34
432x243 59.92 59.57
320x240 60.05
360x202 59.51 59.13
320x180 59.84 59.32
HDMI-1 connected 1920x1080+0+0 (normal left inverted right x ax
1920x1080 60.00 50.00 59.94*
1680x1050 59.88
1280x1024 75.02 60.02
1440x900 59.90
1280x960 60.00
1280x720 60.00 50.00 59.94
1024x768 75.03 70.07 60.00
832x624 74.55
800x600 72.19 75.00 60.32 56.25
720x576 50.00
720x480 60.00 59.94
640x480 75.00 72.81 66.67 60.00 59.94
720x400 70.08
DP-1 disconnected (normal left inverted right x axis y axis)
HDMI-2 disconnected (normal left inverted right x axis y axis)
-
sudo get-edid | parse-edid
This is read-edid version 3.0.2. Prepare for some fun.
Attempting to use i2c interface
No EDID on bus 0
No EDID on bus 2
No EDID on bus 4
No EDID on bus 5
No EDID on bus 6
2 potential busses found: 1 3
Will scan through until the first EDID is found.
Pass a bus number as an option to this program to go only for that one.
256-byte EDID successfully retrieved from i2c bus 1
Looks like i2c was successful. Have a good day.
Checksum Correct
Section "Monitor"
Identifier "U2790B"
ModelName "U2790B"
VendorName "AOC"
# Monitor Manufactured week 38 of 2019
# EDID version 1.3
# Digital Display
DisplaySize 600 340
Gamma 2.20
Option "DPMS" "true"
Horizsync 30-160
VertRefresh 23-80
# Maximum pixel clock is 600MHz
#Not giving standard mode: 1920x1080, 60Hz
#Not giving standard mode: 1680x1050, 60Hz
#Not giving standard mode: 1440x900, 60Hz
#Not giving standard mode: 1280x1024, 60Hz
#Not giving standard mode: 1280x960, 60Hz
#Not giving standard mode: 1280x720, 60Hz
#Extension block found. Parsing...
#WARNING: I may have missed a mode (CEA mode 93)
#WARNING: I may have missed a mode (CEA mode 94)
#WARNING: I may have missed a mode (CEA mode 95)
#WARNING: I may have missed a mode (CEA mode 96)
#WARNING: I may have missed a mode (CEA mode 97)
Modeline "Mode 9" 241.50 2560 2608 2640 2720 1440 1443 1448 1481 +hsync +vsync
Modeline "Mode 0" 533.25 3840 3888 3920 4000 2160 2163 2168 2222 +hsync -vsync
Modeline "Mode 1" 262.75 3840 3888 3920 4000 2160 2163 2168 2191 +hsync -vsync
Modeline "Mode 2" 148.500 1920 2008 2052 2200 1080 1084 1089 1125 +hsync +vsync
Modeline "Mode 3" 74.250 1280 1390 1420 1650 720 725 730 750 +hsync +vsync
Modeline "Mode 4" 27.027 720 736 798 858 480 489 495 525 -hsync -vsync
Modeline "Mode 5" 148.500 1920 2448 2492 2640 1080 1084 1089 1125 +hsync +vsync
Modeline "Mode 6" 74.250 1280 1720 1760 1980 720 725 730 750 +hsync +vsync
Modeline "Mode 7" 25.200 640 656 752 800 480 490 492 525 -hsync -vsync
Modeline "Mode 8" 27.000 720 732 796 864 576 581 586 625 -hsync -vsync
Modeline "Mode 10" 148.50 1920 2008 2052 2200 1080 1084 1089 1125 +hsync +vsync
Modeline "Mode 11" 74.25 1280 1390 1430 1650 720 725 730 750 +hsync +vsync
Modeline "Mode 12" 277.25 1920 1968 2000 2080 2160 2163 2173 2222 +hsync -vsync
Option "PreferredMode" "Mode 9"
EndSection
我没有主意了。感谢您的帮助。
答案1
我差不多解决了。
对于遇到同样问题的人：我手动安装了 NVidia 驱动程序，但所有 ppa 驱动程序都不起作用。为此，我按照说明操作这里。（Nvidia 驱动程序已安装但未在 ubuntu 18.04 上加载） NVidia 现在可以工作了，但仍然没有 4k。事实证明，这不仅仅是 30fps，而且需要降低像素时钟（无法设置正确的显示分辨率）
我认为问题还没有完全解决，因为我的 GPU“应该能够支持”4k@60fps。GeForce 940MX 是一款非常奇怪的型号，我不建议任何人使用它。甚至 NVidia 自己也不清楚是否支持 4k。