USB-C to HDMI: Login screen activates monitor but logging in disables monitor

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6

Hi Fabby, thanks for the heads up. I’ve updated my profile now as required.

Here’s the output of inxi --admin --verbosity=7 --filter --no-host --width:

System:
  Kernel: 5.8.11-1-MANJARO x86_64 bits: 64 compiler: N/A 
  parameters: BOOT_IMAGE=/boot/vmlinuz-5.8-x86_64 
  root=UUID=20873ee3-6da2-4348-bd86-fce85dbf7109 rw quiet apparmor=1 
  security=apparmor resume=UUID=9bde9cdb-63b1-42c7-8d51-ff054ceb9982 
  udev.log_priority=3 
  Desktop: KDE Plasma 5.19.5 tk: Qt 5.15.1 wm: kwin_x11 
  dm: LightDM 1.30.0, SDDM Distro: Manjaro Linux 
Machine:
  Type: Laptop System: Dell product: XPS 13 7390 v: N/A serial: <filter> 
  Chassis: type: 10 serial: <filter> 
  Mobo: Dell model: 0G2D0W v: A00 serial: <filter> UEFI: Dell v: 1.6.0 
  date: 07/07/2020 
Battery:
  ID-1: BAT0 charge: 49.4 Wh condition: 49.4/52.0 Wh (95%) volts: 8.5/7.6 
  model: SMP DELL G8VCF6C type: Li-poly serial: <filter> status: Full 
Memory:
  RAM: total: 15.34 GiB used: 4.76 GiB (31.0%) 
  RAM Report: permissions: Unable to run dmidecode. Root privileges required. 
CPU:
  Topology: Quad Core model: Intel Core i7-10510U bits: 64 type: MT MCP 
  arch: Kaby Lake family: 6 model-id: 8E (142) stepping: C (12) microcode: D6 
  L2 cache: 8192 KiB bogomips: 36812 
  Speed: 800 MHz min/max: 400/4900 MHz Core speeds (MHz): 1: 800 2: 800 3: 795 
  4: 800 5: 800 6: 798 7: 795 8: 799 
  Flags: 3dnowprefetch abm acpi adx aes aperfmperf apic arat arch_capabilities 
  arch_perfmon art avx avx2 bmi1 bmi2 bts clflush clflushopt cmov constant_tsc 
  cpuid cpuid_fault cx16 cx8 de ds_cpl dtes64 dtherm dts epb ept ept_ad erms 
  est f16c flexpriority flush_l1d fma fpu fsgsbase fxsr ht hwp hwp_act_window 
  hwp_epp hwp_notify ibpb ibrs ibrs_enhanced ida intel_pt invpcid 
  invpcid_single lahf_lm lm mca mce md_clear mmx monitor movbe mpx msr mtrr 
  nonstop_tsc nopl nx pae pat pbe pcid pclmulqdq pdcm pdpe1gb pebs pge pln pni 
  popcnt pse pse36 pts rdrand rdseed rdtscp rep_good sdbg sep smap smep ss 
  ssbd sse sse2 sse4_1 sse4_2 ssse3 stibp syscall tm tm2 tpr_shadow tsc 
  tsc_adjust tsc_deadline_timer vme vmx vnmi vpid x2apic xgetbv1 xsave xsavec 
  xsaveopt xsaves xtopology xtpr 
  Vulnerabilities: Type: itlb_multihit status: KVM: VMX disabled 
  Type: l1tf status: Not affected 
  Type: mds status: Not affected 
  Type: meltdown status: Not affected 
  Type: spec_store_bypass 
  mitigation: Speculative Store Bypass disabled via prctl and seccomp 
  Type: spectre_v1 
  mitigation: usercopy/swapgs barriers and __user pointer sanitization 
  Type: spectre_v2 mitigation: Enhanced IBRS, IBPB: conditional, RSB filling 
  Type: srbds mitigation: TSX disabled 
  Type: tsx_async_abort status: Not affected 
Graphics:
  Device-1: Intel UHD Graphics vendor: Dell driver: i915 v: kernel 
  bus ID: 00:02.0 chip ID: 8086:9b41 
  Display: x11 server: X.Org 1.20.9 compositor: kwin_x11 driver: intel 
  unloaded: modesetting alternate: fbdev,vesa display ID: :0 screens: 1 
  Screen-1: 0 s-res: 1920x1080 s-dpi: 96 s-size: 506x285mm (19.9x11.2") 
  s-diag: 581mm (22.9") 
  Monitor-1: eDP1 res: 1920x1080 hz: 60 dpi: 168 size: 290x160mm (11.4x6.3") 
  diag: 331mm (13") 
  OpenGL: renderer: Mesa Intel UHD Graphics (CML GT2) v: 4.6 Mesa 20.1.8 
  direct render: Yes 
Audio:
  Device-1: Intel vendor: Dell driver: snd_hda_intel v: kernel 
  alternate: snd_soc_skl,snd_sof_pci bus ID: 00:1f.3 chip ID: 8086:02c8 
  Sound Server: ALSA v: k5.8.11-1-MANJARO 
Network:
  Device-1: Intel Wi-Fi 6 AX200 vendor: Bigfoot Networks driver: iwlwifi 
  v: kernel port: efa0 bus ID: 02:00.0 chip ID: 8086:2723 
  IF: wlp2s0 state: up mac: <filter> 
  IP v4: <filter> type: dynamic noprefixroute scope: global 
  broadcast: <filter> 
  IP v6: <filter> type: noprefixroute scope: link 
  Device-2: Realtek RTL8153 Gigabit Ethernet Adapter type: USB driver: r8152 
  bus ID: 4-2.3:46 chip ID: 0bda:8153 serial: <filter> 
  IF: ens8u2u3 state: down mac: <filter> 
  WAN IP: <filter> 
Drives:
  Local Storage: total: 476.94 GiB used: 93.85 GiB (19.7%) 
  SMART Message: Required tool smartctl not installed. Check --recommends 
  ID-1: /dev/nvme0n1 vendor: Toshiba model: KXG60ZNV512G NVMe 512GB 
  size: 476.94 GiB block size: physical: 512 B logical: 512 B speed: 31.6 Gb/s 
  lanes: 4 serial: <filter> rev: 10604107 scheme: GPT 
  Message: No Optical or Floppy data was found. 
RAID:
  Message: No RAID data was found. 
Partition:
  ID-1: / raw size: 459.67 GiB size: 451.46 GiB (98.21%) 
  used: 93.82 GiB (20.8%) fs: ext4 dev: /dev/nvme0n1p2 label: N/A 
  uuid: 20873ee3-6da2-4348-bd86-fce85dbf7109 
  ID-2: /boot/efi raw size: 300.0 MiB size: 299.4 MiB (99.80%) 
  used: 33.0 MiB (11.0%) fs: vfat dev: /dev/nvme0n1p1 label: N/A 
  uuid: 5824-77B5 
Swap:
  Kernel: swappiness: 60 (default) cache pressure: 100 (default) 
  ID-1: swap-1 type: partition size: 16.97 GiB used: 0 KiB (0.0%) priority: -2 
  dev: /dev/nvme0n1p3 label: N/A uuid: 9bde9cdb-63b1-42c7-8d51-ff054ceb9982 
Unmounted:
  Message: No unmounted partitions found. 
USB:
  Hub: 1-0:1 info: Full speed (or root) Hub ports: 12 rev: 2.0 speed: 480 Mb/s 
  chip ID: 1d6b:0002 
  Hub: 1-6:30 info: VIA Labs USB2.0 Hub ports: 5 rev: 2.1 speed: 480 Mb/s 
  chip ID: 2109:2817 
  Device-1: 1-6.5:31 info: N/A type: Billboard driver: N/A interfaces: 1 
  rev: 2.0 speed: 480 Mb/s chip ID: 291a:8380 serial: <filter> 
  Device-2: 1-7:3 info: Intel AX200 Bluetooth type: Bluetooth driver: btusb 
  interfaces: 2 rev: 2.0 speed: 12 Mb/s chip ID: 8087:0029 
  Hub: 2-0:1 info: Full speed (or root) Hub ports: 6 rev: 3.1 speed: 10 Gb/s 
  chip ID: 1d6b:0003 
  Hub: 3-0:1 info: Full speed (or root) Hub ports: 2 rev: 2.0 speed: 480 Mb/s 
  chip ID: 1d6b:0002 
  Hub: 4-0:1 info: Full speed (or root) Hub ports: 2 rev: 3.1 speed: 10 Gb/s 
  chip ID: 1d6b:0003 
  Hub: 4-2:44 info: VIA Labs USB3.0 Hub ports: 4 rev: 3.1 speed: 5 Gb/s 
  chip ID: 2109:0817 
  Device-1: 4-2.2:45 info: Genesys Logic SD Card Reader and Writer 
  type: Mass Storage driver: usb-storage interfaces: 1 rev: 3.2 speed: 5 Gb/s 
  chip ID: 05e3:0749 serial: <filter> 
  Device-2: 4-2.3:46 info: Realtek RTL8153 Gigabit Ethernet Adapter 
  type: Network driver: r8152 interfaces: 1 rev: 3.0 speed: 5 Gb/s 
  chip ID: 0bda:8153 serial: <filter> 
Sensors:
  System Temperatures: cpu: 49.0 C mobo: N/A 
  Fan Speeds (RPM): cpu: 0 fan-2: 0 
Info:
  Processes: 266 Uptime: 7d 40m Init: systemd v: 246 Compilers: gcc: 10.2.0 
  alt: 8 clang: 10.0.1 Packages: 1534 pacman: 1525 lib: 452 flatpak: 0 snap: 9 
  Shell: Bash v: 5.0.18 running in: konsole inxi: 3.1.05

And for ls/etc/X11/mhwd.d/ there was nothing returned.

7

I ran xrandr --output VIRTUAL1 --auto and that disconnected my external monitor, resulting in no signal. It has also disabled KDE’s compositor which I have to re-enable with ALT+SHIFT+F12. The laptop’s own monitor continues to work though.

I ran xrandr again though and got this:

Screen 0: minimum 8 x 8, current 1920 x 1080, maximum 32767 x 32767
eDP1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 290mm x 160mm
   1920x1080     60.03*+  48.03  
DP1 disconnected (normal left inverted right x axis y axis)
DP2 disconnected (normal left inverted right x axis y axis)
DP2-1 disconnected (normal left inverted right x axis y axis)
DP2-2 disconnected (normal left inverted right x axis y axis)
DP2-3 disconnected (normal left inverted right x axis y axis)
VIRTUAL1 disconnected (normal left inverted right x axis y axis)
  1920x1080 (0x1b7) 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
  1920x1080 (0x1b8) 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 (0x1b9) 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
  1600x1200 (0x1ba) 162.000MHz +HSync +VSync
        h: width  1600 start 1664 end 1856 total 2160 skew    0 clock  75.00KHz
        v: height 1200 start 1201 end 1204 total 1250           clock  60.00Hz
  1680x1050 (0x1bb) 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 (0x1bc) 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 (0x1bd) 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 (0x1be) 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 (0x1bf) 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
  1366x768 (0x1c0) 85.500MHz +HSync +VSync
        h: width  1366 start 1436 end 1579 total 1792 skew    0 clock  47.71KHz
        v: height  768 start  771 end  774 total  798           clock  59.79Hz
  1152x864 (0x1c1) 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 (0x1c2) 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 (0x1c3) 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 (0x1c4) 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
  1024x768 (0x1c5) 78.750MHz +HSync +VSync
        h: width  1024 start 1040 end 1136 total 1312 skew    0 clock  60.02KHz
        v: height  768 start  769 end  772 total  800           clock  75.03Hz
  1024x768 (0x1c6) 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 (0x1c7) 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
  832x624 (0x1c8) 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 (0x1c9) 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 (0x1ca) 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 (0x1cb) 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 (0x1cc) 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 (0x1cd) 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 (0x1ce) 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 (0x1cf) 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 (0x1d0) 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 (0x1d1) 31.500MHz -HSync -VSync
        h: width   640 start  664 end  704 total  832 skew    0 clock  37.86KHz
        v: height  480 start  489 end  492 total  520           clock  72.81Hz
  640x480 (0x1d2) 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 (0x1d3) 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 (0x1d4) 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 (0x1d5) 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
8

Can you get the output of xrandr with the monitor on?

9

I can’t get the monitor to regain signal and display when connected. Here’s what xrandr is outputting though:

Screen 0: minimum 8 x 8, current 1920 x 1080, maximum 32767 x 32767
eDP1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 290mm x 160mm
   1920x1080     60.03*+  48.03  
DP1 disconnected (normal left inverted right x axis y axis)
DP2 disconnected (normal left inverted right x axis y axis)
DP2-1 connected (normal left inverted right x axis y axis)
   1920x1080     60.00 +  50.00    59.94  
   1600x1200     60.00  
   1680x1050     59.88  
   1280x1024     75.02    60.02  
   1440x900      59.90  
   1280x960      60.00  
   1366x768      59.79  
   1152x864      75.00  
   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  
DP2-2 disconnected (normal left inverted right x axis y axis)
DP2-3 disconnected (normal left inverted right x axis y axis)
VIRTUAL1 disconnected (normal left inverted right x axis y axis)
10

I managed to get the monitor connected by replugging the HDMI cable to the other HDMI port, and replugging the USB-C to the second USB-C port next to the previous. The monitor connects but this time the desktop layout/background were reset. Here are the results of running xrandr afterwards:

Screen 0: minimum 8 x 8, current 1921 x 2160, maximum 32767 x 32767
eDP1 connected primary 1920x1080+0+1080 (normal left inverted right x axis y axis) 290mm x 160mm
   1920x1080     60.03*+  48.03  
DP1 disconnected (normal left inverted right x axis y axis)
DP1-1 disconnected (normal left inverted right x axis y axis)
DP1-2 connected 1920x1080+1+0 (normal left inverted right x axis y axis) 530mm x 300mm
   1920x1080     60.00*+  50.00    59.94  
   1600x1200     60.00  
   1680x1050     59.88  
   1280x1024     75.02    60.02  
   1440x900      59.90  
   1280x960      60.00  
   1366x768      59.79  
   1152x864      75.00  
   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  
DP1-3 disconnected (normal left inverted right x axis y axis)
DP2 disconnected (normal left inverted right x axis y axis)
DP2-1 disconnected (normal left inverted right x axis y axis)
DP2-2 disconnected (normal left inverted right x axis y axis)
DP2-3 disconnected (normal left inverted right x axis y axis)
VIRTUAL1 disconnected (normal left inverted right x axis y axis)
11

And does it retain the signal?

EDIT: when DP2-1 appears, you should be able to turn the monitor on with xrandr --output DP2-1 --auto --left-of eDP1, for example, where --left-of can change according to your preference. See xrandr --help for more info.

12

Since physically altering the cables and running xrandr there has been no loss in signal, not even blackouts.

13

Well, that doesn’t explain why it disappeared…

14

It’s strange because before altering the cables I restarted my laptop and the login screen rendered the monitor and the laptop perfectly with no blackouts; nay if I login the external monitor loses signal with only the laptop remaining. The compositor is disabled upon login.

15

Is this still happening? It could be a faulty port.

16

@mbb

Or a dodgy connection:

  • Cable 1 in port 1, cable 2 in port 2: dodgy connection
  • Cable 1 in port 2 and cable 2 in port 1: fits perfectly.

@7bl Please keep this in mind for the future: if you get this again, the bables or ports might need replacing (Hardware issue)

@mbb Would you mind me giving the solution to this post?

17

It’s not me who you should be asking. You should ask the OP. I personally think it’s still too early.

1 Like
18

That’s why I asked you! :wink:

1 Like
19

Fabby, I don’t think the issue has been resolved. I don’t think there are issues with the ports here. The previous cable layout displayed a rendered login screen on the monitor but a disabled external monitor upon login. I fiddled around with the cables again during login and this time I lost connection to the external monitor. It was only when I replugged the USB-C then disconnected/reconnected the HDMI cable at the same port that I got my external monitor reconnected. I don’t think this is a hardware issue.

1 Like
20

Disable the USB power saving in TLP. You can install TLPUI to configure it.

1 Like
21

That’s had no effect. Looking inside /etc/tlp.conf I changed the entry to USB_AUTOSUSPEND="0".

22

I’m running out of ideas…

1 Like
23

It’s been a while since I responded to this. The underlying issue to this problem is yet to be discovered and yet to be addressed. My suspicions are that kscreen is interfering with the way xrandr handles display output, and there is reason that is the case because this issue manifests whenever I log in to the plasma desktop. To mitigate this problem, however, I’ve added a startup script to simply execute xrandr --output DP2-1 --auto --above eDP1. This alleviates the issue but doesn’t completely resolve it.

I have another laptop that uses Kubuntu. Since that laptop has a HDMI port, there are zero issues with display output on that one. The issue with USB-C to HDMI is also present on that laptop, but not with HDMI alone. So I also suspect it’s an issue with USB-C to HDMI too.

1 Like
24

This is the first time you’re mentioning you’re using an adapter and I’m betting a bottle of :champagne: it’s a passive adapter, and that falls under my previous statement:

  1. Passive adapter: Cheap, does’t have its own power supply, not much documentation (if any), no Linux drivers.
  2. Active adapter: 100+€, has its own power supply and DSP and only converts between well-specified resolutions. (E.G. mine does s-video, VGA, HDMI, DVI input and outputs DVI, VGA and HDMI only and goes up to FHD on HDMI/DVI and HD on VGA. It’s also an old clunker). Doesn’t need any drivers as it’s a hardware solution.

:man_shrugging:

1 Like
25