我有一台能够驱动 4K 屏幕的笔记本电脑（通常驱动 2K 屏幕）。我尝试让它通过 Display Port 输出到 HDMI 输入（两者都能够进行 4K 传输）驱动 4K 电视（LG 55UF7600），但没有成功。但是，Ubuntu 仅提供 1080p 作为其在电视上驱动的最大分辨率（通过nvidia-settings和Settings-> Display）。我很困惑为什么。
我读了一些资料，并尝试通过在 中创建“10-monitor.conf”文件来强制 X 发送/usr/share/X11/xorg.conf.d。但是，这没有用。该文件包含：
Section "Monitor"
Identifier "Monitor0"
Modeline "3840x2160_60.00" 712.75 3840 4160 4576 5312 2160 2163 2168 2237 -HSync +VSync
EndSection
Section "Screen"
Identifier "Screen0"
Device "DP-0"
Monitor "Monitor0"
DefaultDepth 24
SubSection "Display"
Depth 24
Modes "3840x2160" "1920x1080"
EndSubSection
EndSection
我生成Modeline使用：
cvt 3840 2160 60
# 3840x2160 59.98 Hz (CVT 8.29M9) hsync: 134.18 kHz; pclk: 712.75 MHz
Modeline "3840x2160_60.00" 712.75 3840 4160 4576 5312 2160 2163 2168 2237 -hsync +vsync
在创建10-monitor.conf文件之前，我尝试使用以下命令添加模式xrandr：
xrandr --newmode "3840x2160_60.00" 712.75 3840 4160 4576 5312 2160 2163 2168 2237 -HSync +VSync
xrandr --addmode DP-0 3840x2160_60.00
X Error of failed request: BadMatch (invalid parameter attributes)
Major opcode of failed request: 140 (RANDR)
Minor opcode of failed request: 18 (RRAddOutputMode)
Serial number of failed request: 45
Current serial number in output stream: 46
我无法弄清楚该错误信息（对于初学者来说它没有什么帮助）。
以下是我发现的有趣消息/var/log/Xorg.0.log：
[ 341.357] (**) NVIDIA(0): Using HorizSync/VertRefresh ranges from the EDID for display
[ 341.357] (**) NVIDIA(0): device LG Electronics LG TV (DFP-0) (Using EDID
[ 341.357] (**) NVIDIA(0): frequencies has been enabled on all display devices.)
[ 341.358] (WW) NVIDIA(GPU-0): The EDID for LG Electronics LG TV (DFP-0) contradicts itself:
[ 341.358] (WW) NVIDIA(GPU-0): mode "1920x1080" is specified in the EDID; however, the
[ 341.358] (WW) NVIDIA(GPU-0): EDID's valid VertRefresh range (58.000-62.000 Hz) would
[ 341.358] (WW) NVIDIA(GPU-0): exclude this mode's VertRefresh (30.0 Hz); ignoring
[ 341.358] (WW) NVIDIA(GPU-0): VertRefresh check for mode "1920x1080".
[ 341.358] (WW) NVIDIA(GPU-0): The EDID for LG Electronics LG TV (DFP-0) contradicts itself:
[ 341.358] (WW) NVIDIA(GPU-0): mode "1920x1080" is specified in the EDID; however, the
[ 341.358] (WW) NVIDIA(GPU-0): EDID's valid HorizSync range (30.000-83.000 kHz) would
[ 341.358] (WW) NVIDIA(GPU-0): exclude this mode's HorizSync (27.0 kHz); ignoring
[ 341.358] (WW) NVIDIA(GPU-0): HorizSync check for mode "1920x1080".
[ 341.358] (WW) NVIDIA(GPU-0): The EDID for LG Electronics LG TV (DFP-0) contradicts itself:
[ 341.358] (WW) NVIDIA(GPU-0): mode "1920x1080" is specified in the EDID; however, the
[ 341.358] (WW) NVIDIA(GPU-0): EDID's valid VertRefresh range (58.000-62.000 Hz) would
[ 341.358] (WW) NVIDIA(GPU-0): exclude this mode's VertRefresh (24.0 Hz); ignoring
[ 341.358] (WW) NVIDIA(GPU-0): VertRefresh check for mode "1920x1080".
[ 369.265] (II) NVIDIA(0): Setting mode "NULL"
[ 369.535] (II) NVIDIA(0): Setting mode "DP-0: nvidia-auto-select @1920x1080 +0+0 {ViewPortIn=1920x1080, ViewPortOut=1920x1080+0+0}"
我猜是电视发送了错误的 EDID，声称仅支持 1080p。我尝试将此选项添加到我的10-monitor.conf文件中：
Option "UseEDID" "FALSE"
但这只是杀死了 X。它根本无法启动（蓝屏，无法登录）。
我尝试使用 get/parse-edid 软件，但是我一定是没有正确使用它，因为我无法获取任何 EDID。
为了完整起见，我的 xrandr 输出是：
Screen 0: minimum 8 x 8, current 1920 x 1080, maximum 16384 x 16384
VGA-0 disconnected (normal left inverted right x axis y axis)
DP-0 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 1600mm x 900mm
1920x1080 60.0*+ 59.9 30.0 24.0 60.1 60.0
1360x768 60.0
1280x1024 60.0
1280x720 60.0 59.9
1152x864 60.0
1024x768 60.0
800x600 60.3
720x480 59.9
640x480 60.0 59.9 59.9
DP-1 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)
DP-3 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 194mm
1920x1080 60.0*+ 40.0
DP-4 disconnected (normal left inverted right x axis y axis)
DP-5 disconnected (normal left inverted right x axis y axis)
DP-6 disconnected (normal left inverted right x axis y axis)
3840x2160_60.00 (0x335) 712.8MHz
h: width 3840 start 4160 end 4576 total 5312 skew 0 clock 134.2KHz
v: height 2160 start 2163 end 2168 total 2237 clock 60.0Hz
smm@smmlaptop:/usr/share/X11/xorg.conf.d$ xrandr --addmode DP-0 3840x2160_60.00
X Error of failed request: BadMatch (invalid parameter attributes)
Major opcode of failed request: 140 (RANDR)
Minor opcode of failed request: 18 (RRAddOutputMode)
Serial number of failed request: 45
Current serial number in output stream: 46
smm@smmlaptop:/usr/share/X11/xorg.conf.d$ xrandr
Screen 0: minimum 8 x 8, current 1920 x 1080, maximum 16384 x 16384
VGA-0 disconnected (normal left inverted right x axis y axis)
DP-0 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 1600mm x 900mm
1920x1080 60.0*+ 59.9 30.0 24.0 60.1 60.0
1360x768 60.0
1280x1024 60.0
1280x720 60.0 59.9
1152x864 60.0
1024x768 60.0
800x600 60.3
720x480 59.9
640x480 60.0 59.9 59.9
DP-1 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)
DP-3 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 194mm
1920x1080 60.0*+ 40.0
DP-4 disconnected (normal left inverted right x axis y axis)
DP-5 disconnected (normal left inverted right x axis y axis)
DP-6 disconnected (normal left inverted right x axis y axis)
3840x2160_60.00 (0x335) 712.8MHz
h: width 3840 start 4160 end 4576 total 5312 skew 0 clock 134.2KHz
v: height 2160 start 2163 end 2168 total 2237 clock 60.0Hz
非常感谢您的帮助！提前致谢。
答案1
我有一台 55 英寸 4K 三星电视和一台 Acer 4K 便携式电脑，都配有 HDMI 端口。我有两根不同的 HDMI 电缆。其中一根不工作，但另一根工作得很好。只需尝试更换更好的电缆即可。