我的主板上有 4 个物理端口：VGA、HDMI、DVI 和 DisplayPort。通常我使用 HDMI 和 DVI，但我想切换到 HDMI 和 DP。但是，xrandr 的输出显示 DP 始终断开连接：
$ xrandr --verbose
Screen 0: minimum 8 x 8, current 3840 x 1080, maximum 32767 x 32767
DP1 disconnected (normal left inverted right x axis y axis)
Identifier: 0x43
Timestamp: 284401515
Subpixel: unknown
Clones: HDMI3
CRTCs: 0 1 2
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
Broadcast RGB: Automatic
supported: Automatic, Full, Limited 16:235
audio: auto
supported: force-dvi, off, auto, on
1920x1080 (0x4a) 148.500MHz +HSync +VSync
h: width 1920 start 2008 end 2052 total 2200 skew 0 clock 67.50KHz
v: height 1080 start 1084 end 1089 total 1125 clock 60.00Hz
HDMI1 connected primary 1920x1080+1920+0 (0x4a) normal (normal left inverted right x axis y axis) 509mm x 286mm
Identifier: 0x44
Timestamp: 284401515
Subpixel: unknown
Gamma: 1.0:1.0:1.0
Brightness: 1.0
Clones:
CRTC: 0
CRTCs: 0 1 2
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
EDID:
00ffffffffffff000469d223e3a40000
2417010380331d782ad945a2554da027
125054b7ef00d1c0814081809500b300
714f81c08100023a801871382d40582c
4500fd1e1100001e000000ff0044394c
4d54463034323231310a000000fd0032
4b185311000a202020202020000000fc
00415355532056533233390a20200140
020322714f0102031112130414050e0f
1d1e1f10230917078301000065030c00
10008c0ad08a20e02d10103e9600fd1e
11000018011d007251d01e206e285500
fd1e1100001e011d00bc52d01e20b828
5540fd1e1100001e8c0ad09020403120
0c405500fd1e11000018000000000000
000000000000000000000000000000e9
aspect ratio: Automatic
supported: Automatic, 4:3, 16:9
Broadcast RGB: Automatic
supported: Automatic, Full, Limited 16:235
audio: auto
supported: force-dvi, off, auto, on
1920x1080 (0x4a) 148.500MHz +HSync +VSync *current +preferred
h: width 1920 start 2008 end 2052 total 2200 skew 0 clock 67.50KHz
v: height 1080 start 1084 end 1089 total 1125 clock 60.00Hz
1920x1080 (0xe6) 148.500MHz +HSync +VSync
h: width 1920 start 2448 end 2492 total 2640 skew 0 clock 56.25KHz
v: height 1080 start 1084 end 1089 total 1125 clock 50.00Hz
1920x1080 (0xe7) 148.352MHz +HSync +VSync
h: width 1920 start 2008 end 2052 total 2200 skew 0 clock 67.43KHz
v: height 1080 start 1084 end 1089 total 1125 clock 59.94Hz
1920x1080i (0xe8) 74.250MHz +HSync +VSync Interlace
h: width 1920 start 2008 end 2052 total 2200 skew 0 clock 33.75KHz
v: height 1080 start 1084 end 1094 total 1125 clock 60.00Hz
1920x1080i (0xe9) 74.250MHz +HSync +VSync Interlace
h: width 1920 start 2448 end 2492 total 2640 skew 0 clock 28.12KHz
v: height 1080 start 1084 end 1094 total 1125 clock 50.00Hz
1920x1080i (0xea) 74.176MHz +HSync +VSync Interlace
h: width 1920 start 2008 end 2052 total 2200 skew 0 clock 33.72KHz
v: height 1080 start 1084 end 1094 total 1125 clock 59.94Hz
1680x1050 (0xeb) 119.000MHz +HSync -VSync
h: width 1680 start 1728 end 1760 total 1840 skew 0 clock 64.67KHz
v: height 1050 start 1053 end 1059 total 1080 clock 59.88Hz
1280x1024 (0xec) 135.000MHz +HSync +VSync
h: width 1280 start 1296 end 1440 total 1688 skew 0 clock 79.98KHz
v: height 1024 start 1025 end 1028 total 1066 clock 75.02Hz
1280x1024 (0xed) 108.000MHz +HSync +VSync
h: width 1280 start 1328 end 1440 total 1688 skew 0 clock 63.98KHz
v: height 1024 start 1025 end 1028 total 1066 clock 60.02Hz
1440x900 (0xee) 88.750MHz +HSync -VSync
h: width 1440 start 1488 end 1520 total 1600 skew 0 clock 55.47KHz
v: height 900 start 903 end 909 total 926 clock 59.90Hz
1280x960 (0xef) 108.000MHz +HSync +VSync
h: width 1280 start 1376 end 1488 total 1800 skew 0 clock 60.00KHz
v: height 960 start 961 end 964 total 1000 clock 60.00Hz
1280x800 (0xf0) 71.000MHz +HSync -VSync
h: width 1280 start 1328 end 1360 total 1440 skew 0 clock 49.31KHz
v: height 800 start 803 end 809 total 823 clock 59.91Hz
1152x864 (0xf1) 108.000MHz +HSync +VSync
h: width 1152 start 1216 end 1344 total 1600 skew 0 clock 67.50KHz
v: height 864 start 865 end 868 total 900 clock 75.00Hz
1280x720 (0xf2) 74.250MHz +HSync +VSync
h: width 1280 start 1390 end 1430 total 1650 skew 0 clock 45.00KHz
v: height 720 start 725 end 730 total 750 clock 60.00Hz
1280x720 (0xf3) 74.250MHz +HSync +VSync
h: width 1280 start 1720 end 1760 total 1980 skew 0 clock 37.50KHz
v: height 720 start 725 end 730 total 750 clock 50.00Hz
1280x720 (0xf4) 74.176MHz +HSync +VSync
h: width 1280 start 1390 end 1430 total 1650 skew 0 clock 44.96KHz
v: height 720 start 725 end 730 total 750 clock 59.94Hz
1440x576 (0xf5) 54.000MHz -HSync -VSync
h: width 1440 start 1464 end 1592 total 1728 skew 0 clock 31.25KHz
v: height 576 start 581 end 586 total 625 clock 50.00Hz
1024x768 (0xf6) 78.800MHz +HSync +VSync
h: width 1024 start 1040 end 1136 total 1312 skew 0 clock 60.06KHz
v: height 768 start 769 end 772 total 800 clock 75.08Hz
1024x768 (0xf7) 75.000MHz -HSync -VSync
h: width 1024 start 1048 end 1184 total 1328 skew 0 clock 56.48KHz
v: height 768 start 771 end 777 total 806 clock 70.07Hz
1024x768 (0xf8) 65.000MHz -HSync -VSync
h: width 1024 start 1048 end 1184 total 1344 skew 0 clock 48.36KHz
v: height 768 start 771 end 777 total 806 clock 60.00Hz
1440x480 (0xf9) 54.054MHz -HSync -VSync
h: width 1440 start 1472 end 1596 total 1716 skew 0 clock 31.50KHz
v: height 480 start 489 end 495 total 525 clock 60.00Hz
1440x480 (0xfa) 54.000MHz -HSync -VSync
h: width 1440 start 1472 end 1596 total 1716 skew 0 clock 31.47KHz
v: height 480 start 489 end 495 total 525 clock 59.94Hz
832x624 (0xfb) 57.284MHz -HSync -VSync
h: width 832 start 864 end 928 total 1152 skew 0 clock 49.73KHz
v: height 624 start 625 end 628 total 667 clock 74.55Hz
800x600 (0xfc) 50.000MHz +HSync +VSync
h: width 800 start 856 end 976 total 1040 skew 0 clock 48.08KHz
v: height 600 start 637 end 643 total 666 clock 72.19Hz
800x600 (0xfd) 49.500MHz +HSync +VSync
h: width 800 start 816 end 896 total 1056 skew 0 clock 46.88KHz
v: height 600 start 601 end 604 total 625 clock 75.00Hz
800x600 (0xfe) 40.000MHz +HSync +VSync
h: width 800 start 840 end 968 total 1056 skew 0 clock 37.88KHz
v: height 600 start 601 end 605 total 628 clock 60.32Hz
800x600 (0xff) 36.000MHz +HSync +VSync
h: width 800 start 824 end 896 total 1024 skew 0 clock 35.16KHz
v: height 600 start 601 end 603 total 625 clock 56.25Hz
720x576 (0x100) 27.000MHz -HSync -VSync
h: width 720 start 732 end 796 total 864 skew 0 clock 31.25KHz
v: height 576 start 581 end 586 total 625 clock 50.00Hz
720x480 (0x101) 27.027MHz -HSync -VSync
h: width 720 start 736 end 798 total 858 skew 0 clock 31.50KHz
v: height 480 start 489 end 495 total 525 clock 60.00Hz
720x480 (0x102) 27.000MHz -HSync -VSync
h: width 720 start 736 end 798 total 858 skew 0 clock 31.47KHz
v: height 480 start 489 end 495 total 525 clock 59.94Hz
640x480 (0x103) 31.500MHz -HSync -VSync
h: width 640 start 656 end 720 total 840 skew 0 clock 37.50KHz
v: height 480 start 481 end 484 total 500 clock 75.00Hz
640x480 (0x104) 30.240MHz -HSync -VSync
h: width 640 start 704 end 768 total 864 skew 0 clock 35.00KHz
v: height 480 start 483 end 486 total 525 clock 66.67Hz
640x480 (0x105) 25.200MHz -HSync -VSync
h: width 640 start 656 end 752 total 800 skew 0 clock 31.50KHz
v: height 480 start 490 end 492 total 525 clock 60.00Hz
640x480 (0x106) 25.175MHz -HSync -VSync
h: width 640 start 656 end 752 total 800 skew 0 clock 31.47KHz
v: height 480 start 490 end 492 total 525 clock 59.94Hz
720x400 (0x107) 28.320MHz -HSync +VSync
h: width 720 start 738 end 846 total 900 skew 0 clock 31.47KHz
v: height 400 start 412 end 414 total 449 clock 70.08Hz
HDMI2 disconnected (normal left inverted right x axis y axis)
Identifier: 0x45
Timestamp: 284401515
Subpixel: unknown
Clones:
CRTCs: 0 1 2
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
aspect ratio: Automatic
supported: Automatic, 4:3, 16:9
Broadcast RGB: Automatic
supported: Automatic, Full, Limited 16:235
audio: auto
supported: force-dvi, off, auto, on
HDMI3 disconnected (normal left inverted right x axis y axis)
Identifier: 0x46
Timestamp: 284401515
Subpixel: unknown
Clones: DP1
CRTCs: 0 1 2
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
aspect ratio: Automatic
supported: Automatic, 4:3, 16:9
Broadcast RGB: Automatic
supported: Automatic, Full, Limited 16:235
audio: auto
supported: force-dvi, off, auto, on
1920x1080 (0x4a) 148.500MHz +HSync +VSync
h: width 1920 start 2008 end 2052 total 2200 skew 0 clock 67.50KHz
v: height 1080 start 1084 end 1089 total 1125 clock 60.00Hz
VGA1 disconnected (normal left inverted right x axis y axis)
Identifier: 0x47
Timestamp: 284401515
Subpixel: unknown
Clones:
CRTCs: 0 1 2
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
VIRTUAL1 disconnected (normal left inverted right x axis y axis)
Identifier: 0x48
Timestamp: 284401515
Subpixel: no subpixels
Clones:
CRTCs: 3
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
我得到的最接近的是手动添加模式然后尝试切换到它：
$ xrandr --addmode DP1 1920x1080
$ xrandr --auto --output HDMI1 --mode 1920x1080 --primary --output DP1 --mode 1920x1080 --left-of HDMI1 --output VGA1 --off
xrandr: Configure crtc 1 failed
X Error of failed request: BadMatch (invalid parameter attributes)
Major opcode of failed request: 140 (RANDR)
Minor opcode of failed request: 21 (RRSetCrtcConfig)
Serial number of failed request: 47
Current serial number in output stream: 47
现在，当我的第二台显示器插入 DVI 端口时，xrandr 的输出是：
$ xrandr
Screen 0: minimum 8 x 8, current 3840 x 1080, maximum 32767 x 32767
DP1 disconnected (normal left inverted right x axis y axis)
1920x1080 60.00
HDMI1 connected primary 1920x1080+1920+0 (normal left inverted right x axis y axis) 509mm x 286mm
1920x1080 60.00*+ 50.00 59.94
1920x1080i 60.00 50.00 59.94
1680x1050 59.88
1280x1024 75.02 60.02
1440x900 59.90
1280x960 60.00
1280x800 59.91
1152x864 75.00
1280x720 60.00 50.00 59.94
1440x576 50.00
1024x768 75.08 70.07 60.00
1440x480 60.00 59.94
832x624 74.55
800x600 72.19 75.00 60.32 56.25
720x576 50.00
720x480 60.00 59.94
640x480 75.00 66.67 60.00 59.94
720x400 70.08
HDMI2 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 509mm x 286mm
1920x1080 60.00*+ 50.00 59.94
1920x1080i 60.00 50.00 59.94
1680x1050 59.88
1280x1024 75.02 60.02
1440x900 59.90
1280x960 60.00
1280x800 59.91
1152x864 75.00
1280x720 60.00 50.00 59.94
1440x576 50.00
1024x768 75.08 70.07 60.00
1440x480 60.00 59.94
832x624 74.55
800x600 72.19 75.00 60.32 56.25
720x576 50.00
720x480 60.00 59.94
640x480 75.00 66.67 60.00 59.94
720x400 70.08
HDMI3 disconnected (normal left inverted right x axis y axis)
1920x1080 60.00
VGA1 disconnected (normal left inverted right x axis y axis)
VIRTUAL1 disconnected (normal left inverted right x axis y axis)
司机信息：
$ sudo lshw -c video
*-display
description: VGA compatible controller
product: Xeon E3-1200 v3/4th Gen Core Processor Integrated Graphics Controller
vendor: Intel Corporation
physical id: 2
bus info: pci@0000:00:02.0
version: 06
width: 64 bits
clock: 33MHz
capabilities: msi pm vga_controller bus_master cap_list rom
configuration: driver=i915 latency=0
resources: irq:29 memory:f0000000-f03fffff memory:e0000000-efffffff ioport:f000(size=64)
$ modinfo i915
filename: /lib/modules/4.4.0-91-generic/kernel/drivers/gpu/drm/i915/i915.ko
license: GPL and additional rights
description: Intel Graphics
author: Intel Corporation
author: Tungsten Graphics, Inc.
firmware: i915/bxt_dmc_ver1.bin
firmware: i915/skl_dmc_ver1.bin
firmware: i915/skl_guc_ver4.bin
srcversion: F88AC02BE47BB41FC2F1D77
...
我不确定调试的下一步是什么。我以前从未使用过 DisplayPort，因此这很可能是英特尔驱动程序的问题。
编辑：澄清我的端口。 HDMI1 是我实际的 HDMI 端口，HDMI2 是我的 DVI 端口，HDMI3 似乎是 DP1 的克隆，DP1 是我的 DisplayPort。 HDMI1和HDMI2工作正常，但DP1和HDMI3总是显示断开连接。
答案1
# inxi -SGay# inxi -SGIay
System:
Host: ab85m Kernel: 5.8.14-1-default x86_64 bits: 64 compiler: gcc v: 10.2.1
parameters: mitigations=auto consoleblank=0 video=1440x900@60
Desktop: Trinity R14.0.8 tk: Qt 3.5.0 info: kicker wm: Twin 3.0 dm: TDM
Distro: openSUSE Tumbleweed 20201014
Machine:
Type: Desktop System: ASUS product: All Series v: N/A serial: N/A
Mobo: ASUSTeK model: B85M-E v: Rev X.0x serial: MB-1234567890
UEFI: American Megatrends v: 3602 date: 04/04/2018
Graphics:
Device-1: **Intel Xeon E3-1200 v3/4th Gen Core** Processor Integrated Graphics
vendor: ASUSTeK **driver: i915** v: kernel bus ID: 00:02.0 **chip ID: 8086:0402**
Display: **x11 server: X.Org 1.20.9 driver: modesetting** unloaded: fbdev,vesa
alternate: intel display ID: :0 screens: 1
Screen-1: 0 s-res: 2560x2520 s-dpi: 120 s-size: 541x533mm (21.3x21.0")
s-diag: 759mm (29.9")
**Monitor-1: DP-1** res: 2560x1440 hz: 60 dpi: 109 size: 598x336mm (23.5x13.2")
diag: 686mm (27")
**Monitor-2: HDMI-3** res: 2560x1080 hz: 60 dpi: 97 size: 673x284mm (26.5x11.2")
diag: 730mm (28.8")
OpenGL: renderer: Mesa DRI Intel HD Graphics (HSW GT1) v: 4.5 Mesa 20.1.8
compat-v: 3.0 direct render: Yes
Info:...running in: konsole inxi: 3.1.08
# xrandr --listproviders
Providers: number : 1
Provider 0: id: 0x47; cap: 0xf (Source Output, Sink Output, Source Offload, Sink Offload); crtcs: 3; outputs: 5; associated providers: 0; name: modesetting
output VGA-1
output DP-1
output HDMI-1
output HDMI-2
output HDMI-3
# xrandr | egrep 'onnect|creen|\*' | grep -v disconn | sort -r
Screen 0: minimum 320 x 200, current 2560 x 2520, maximum 16384 x 16384
HDMI-3 connected 2560x1080+0+0 (normal left inverted right x axis y axis) 673mm x 284mm
DP-1 connected primary 2560x1440+0+1080 (normal left inverted right x axis y axis) 598mm x 336mm
2560x1440 59.95*+ 74.92
2560x1080 60.00*+
看来我可能有与OP相同的硬件，虽然可能不是相同的主板，而且几乎肯定不是相同的BIOS，但它确实按预期工作。当使用 DVI 电缆而不是 DisplayPort 时，它显示为连接到 HDMI-2。使用时 VGA 显示为 DP-2。
请注意 CRTC 名称的差异。这是使用先进技术上游默认 DDX 驱动程序模式设置而不是较旧技术的 Intel DDX 驱动程序的结果。切换到模式设置 DDX 可能会解决此问题，只需删除提供 Intel DDX 驱动程序的软件包并重新启动 X 即可。
我怀疑更可能的根本问题是 BIOS 有缺陷，但我会先尝试另一个（不相关的；实时的）发行版或两个，以及模式设置 DDX，然后再将 BIOS 视为原因。