Second monitor connected as DVI enters sleep mode during boot (and never comes out of sleep); but works with VGA connection

emacsomancer · 05-18-2019, 04:36 PM

I got a 'new' old monitor, an HP L1750 (1280x1024; VGA & DVI inputs), to use as a secondary display† on my desktop. Unfortunately, when I plugged it in via DVI, it did not seem to detect the monitor and just said "No Input Signal" and then "Entering Sleep Mode".

But when rebooting, it would initially display, until the late Kernel Mode Setting kicks in, and then it would enter sleep mode again. I tried enabling early KMS, but that just makes it enter sleep mode earlier in the boot process.

If I use `nomodeset` as a kernel option, it remains displaying text, but I can never enter an actual graphical display (i.e. my DM refuses to initialise).

I do have it 'working' via a workaround: using an HDMI->VGA connector to connect via the monitor's VGA port to one of my video card's HDMI ports. This works, but it would seem ideal to get a digital rather than analogue connection if possible.

Relevant system information:
================

* OS: Arch Linux
* GPU: MSI Radeon RX 480 Gaming X (AMD)
* Problematic display: HP L1750 (1280x1024@60)
* Problematic connection: DVI-D-0 (works via HDMI-A-0 with HDMI->VGA shim)

† This replaces an old Dell monitor that had served in this capacity, which apparently had a LCD display ribbon cable coming unglued for some time; strategically squeezing the screen sort of fixed it for a while, but eventually horrible display and banding led me to look for a 'new' old monitor.

mrmazda · 05-18-2019, 08:13 PM

I do a lot of PC, display and cable switching here. What you describe is not uncommon. First thing to do software side for greeter and WM/DE is make sure that RX480 is using the amdgpu DDX or modesetting DDX rather than radeon DDX. Sometimes going black after KMS engages is limited to the vttys, lighting back up when the GUI is running.

An /etc/X11/xorg.conf file with appropriate HorizSync and VertRefresh ranges specified might make it light up when reaching greeter/WM/DE when it otherwise does not.

Nomodeset is a workaround designed to enable repairs. With some proprietary video driver versions is required. It disables the very kernel modesetting functionality that all FOSS DDX for the big three brands and several minors require.

Displays can be forced to a specific mode via kernel cmdline. Likely adding video=DVI-D-0:1280x1024@60e would do what you need with a DVI to DVI cable. Note that a change in DDX may change the DVI output name. Xrandr can report the current names. With modesetting it's likely to be DVI-D-1 or DVI-I-1. Radeon DDX likes to name the first *-0, as does the amdgpu DDX.

A display as old as HP L1750 might well have a bad electrolytic capacitor that affects the DVI port but not the VGA, letting bad EDID info reach the kernel only from the digital side.

If you need additional help, please provide output from 'inxi -Gxx'. Pastebinning /var/log/Xorg.0.log might also be useful if none of the above is enough help.

emacsomancer · 05-19-2019, 12:02 AM

Thanks for the extensive reply.

Yes, I have been using amdgpu DDX. Here is my `inxi -Gxx`:

Code:

Graphics:  Device-1: Advanced Micro Devices [AMD/ATI] Ellesmere [Radeon RX 470/480/570/570X/580/580X/590] 
           vendor: Micro-Star MSI driver: amdgpu v: kernel bus ID: 01:00.0 chip ID: 1002:67df 
           Display: x11 server: X.Org 1.20.4 driver: amdgpu unloaded: modesetting alternate: ati,fbdev,vesa 
           compositor: kwin_x11 resolution: 1920x1080~60Hz 
           OpenGL: renderer: AMD Radeon RX 480 Graphics (POLARIS10 DRM 3.30.0 5.1.2-arch1-1-ARCH LLVM 8.0.0) 
           v: 4.5 Mesa 19.0.4 direct render: Yes

I tried adding

Code:

video=DVI-D-0:1280x1024@60e

via the kernel boot options, but unfortunately that did not help - again, the L1750 displayed fine up until KMS, and then displayed the 'sleep' message. (I checked `xrandr`, and indeed the display should be `DVI-D-0`.)

Here is a pastebin of `/var/log/Xorg.0.log`, in case it might reveal something: https://paste.debian.net/1082125/

(HDMI-A-1 is my primary monitor. HDMI-A-0 was unplugged at the time of this log, just to make sure, but is usually where the L1750 is plugged in, via an HDMI->VGA connector.)

mrmazda · 05-19-2019, 02:54 AM

Quote:

Originally Posted by emacsomancer

...Here is a pastebin of `/var/log/Xorg.0.log`, in case it might reveal something:...

I can't think of a way Xorg.0.log could help unless all the connections and displays that should work are actually connected in the manner expected to work .

Try video=DVI-D-0:1280x1024M@60 instead of video=DVI-D-0:1280x1024@60e, and if that doesn't work, try video=DVI-D-0:1280x1024R@60.

Something else to try, after you've logged into the GUI:

Code:

xrandr --output DVI-D-0 --mode 1280x1024@60

If that fails too, see if any mode will light it up, e.g.:

Code:

xrandr --output DVI-D-0 --mode 1024x768

Do dmesg or

Code:

journalctl -b | grep ailed

or

Code:

journalctl -b _COMM=Xorg

provide any hints to a video problem?

Shadow_7 · 05-19-2019, 04:39 AM

Oddness to me is often hardware. Try a different cable?

Otherwise you could try to xrandr around a bit. On my laptop I tend to --off for the laptops LCD when I use an external monitor. So try --on or other options. Or at least see if xrandr without parms "sees" the monitor.

$ xrandr --output DVI-D-0 --on

Although per the previous setting a mode would also turn it on, and not sure if --on is an option even though --off most definitely is. I know that DVI over an HDMI connection can be quirky, at least with sbc computers. It often requires hard coding the specs since the conversion not only looses audio, but also the EDID information an OS needs to understand what it is connected to.

emacsomancer · 05-19-2019, 10:51 AM

Quote:

Originally Posted by mrmazda

I can't think of a way Xorg.0.log could help unless all the connections and displays that should work are actually connected in the manner expected to work .

You misunderstand me. My point was that I plugged everything in the way it should work, i.e. DVI cable from video card to L1750, and just unplugged the HDMI->VGA workaround I had set up, just in case it somehow could affect things.

Quote:

Originally Posted by mrmazda

Try video=DVI-D-0:1280x1024M@60 instead of video=DVI-D-0:1280x1024@60e, and if that doesn't work, try video=DVI-D-0:1280x1024R@60.

Unfortunately, no different results

Quote:

Originally Posted by mrmazda

Something else to try, after you've logged into the GUI:

Code:

xrandr --output DVI-D-0 --mode 1280x1024@60

If that fails too, see if any mode will light it up, e.g.:

Code:

xrandr --output DVI-D-0 --mode 1024x768

Code:

$ xrandr --output DVI-D-0 --mode 1280x1024@60
xrandr: cannot find mode 1280x1024@60

Code:

$ xrandr --output DVI-D-0 --mode 1024x768
xrandr: cannot find mode 1024x768

Quote:

Originally Posted by mrmazda

Do dmesg or

Code:

journalctl -b | grep ailed

or

Code:

journalctl -b _COMM=Xorg

provide any hints to a video problem?

Unfortunately not. All of those either produce no output, or else produce output which are nothing to do with video.

Edit to add: in general, once past KMS, it seems that the video card detects no DVI connection at all, i.e.:

Code:

$ xrandr
Screen 0: minimum 320 x 200, current 3200 x 1080, maximum 16384 x 16384
DisplayPort-0 disconnected (normal left inverted right x axis y axis)
DisplayPort-1 disconnected (normal left inverted right x axis y axis)
HDMI-A-0 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 340mm x 270mm
   1280x1024     60.02 +  75.02* 
   1920x1080     60.00    59.94  
   1280x800      60.02  
   1152x864      75.00  
   1280x720      60.00    59.94  
   1024x768      75.03    70.07    60.00  
   832x624       74.55  
   800x600       72.19    75.00    60.32  
   720x480       60.00    59.94  
   640x480       75.00    72.81    60.00    59.94  
   720x400       70.08  
HDMI-A-1 connected primary 1920x1080+1280+0 (normal left inverted right x axis y axis) 531mm x 299mm
   1920x1080     60.00*+  50.00    59.94    59.99  
   1600x1200     60.00  
   1680x1050     59.88  
   1280x1024     75.02    60.02  
   1440x900      59.90  
   1280x960      60.00  
   1366x768      59.79  
   1280x800      60.00  
   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  
DVI-D-0 disconnected (normal left inverted right x axis y axis)

emacsomancer · 05-19-2019, 10:54 AM

Quote:

Originally Posted by Shadow_7

Oddness to me is often hardware. Try a different cable?

Otherwise you could try to xrandr around a bit. On my laptop I tend to --off for the laptops LCD when I use an external monitor. So try --on or other options. Or at least see if xrandr without parms "sees" the monitor.

$ xrandr --output DVI-D-0 --on

I can look for a different cable, but this is the cable that powered another older monitor for a number of years without issue, so it seems doubtful that the cable is problematic.

xrandr doesn't understand --on as an option, it seems.

Quote:

I know that DVI over an HDMI connection can be quirky, at least with sbc computers.

I'm not doing any HDMI->DVI. I'm just plugging a DVI cable from the DVI-D-out of my video card to the DVI port of the L1750. (My current workaround, since the DVI connection isn't working, is HDMI->VGA, but there's no HDMI->DVI involved in the setup anywhere.)

mrmazda · 05-19-2019, 11:41 AM

Using only DVI, will the HP display stay on if it is the only connected display?

Does it behave any differently if xf86-video-amdgpu and xf86-video-ati are not installed?

emacsomancer · 05-19-2019, 12:15 PM

Quote:

Originally Posted by mrmazda

Using only DVI, will the HP display stay on if it is the only connected display?

Does it behave any differently if xf86-video-amdgpu and xf86-video-ati are not installed?

I've now tried different combinations of having xf86-video-amdgpu and/or xf86-video-ati installed and it makes no difference.

For what happens if it is the L1750 via DVI is the only connected display, oddly the monitor itself remains 'on' (not in 'sleep'); that is, the light stays green rather than turning orange and if I go into the hardware menu it reports that the DVI connection is 'active', but still doesn't actually display anything on screen after KMS.

mrmazda · 05-19-2019, 01:38 PM

Have you tried with a live media boot of some other distro?

Can you find another DVI output somewhere to test that HP display? This seems most likely to be a bad DVI input on the HP, nothing solvable via software.

Shadow_7 · 05-19-2019, 08:10 PM

Have you tried unplugging and re-plugging the DVI cable while in the KMS side of things? Long ago I had a udev issue with usb keyboard and usb mouse in avlinux. Unplug + replug was the work around. Eventually I fiddled enough with installing the next gen udev stuff over the existing stuff and it eventually worked without the work-around. So it was definitely a generational software issue. Beyond hot plugging the monitor after boot, you might give a few other distros a try, as others have suggested. I've always had issues with X defaulting to the lowest common denominator of resolutions, but I know enough xrandr tricks to make it work. And it wasn't an issue in more bleeding edge distros like arch.

Shadow_7 · 05-19-2019, 08:15 PM

You might see if that monitors menus has a select input source. And select DVI of course. I've had issues where one DVI monitor would power down to save power and on restore it would select another mode. Although I had two different PCs hooked up to it at the time. Both on. Probably not your issue, but something to look into.

mrmazda · 05-20-2019, 01:20 AM

Until such time as the HP can be connected to some other DVI output to confirm it can work as expected, let's try to get it to light up in Xorg. First, save the following as /etc/X11/xorg.conf:

Code:

Section "Device"
	Identifier	"DefaultDevice"
EndSection

Section "Monitor"
	Identifier	"DefaultMonitor"
	HorizSync	30-81
	VertRefresh	59-61
	Option		"TargetRefreshRate"	"60"
	Option		"DDC"	"off"
	Option		"DPMS"	"off"
	Option		"DefaultModes"	"on"
	Option		"PreferredMode"	"1280x1024"
EndSection

Section "Screen"
	Identifier	"DefaultScreen"
	Device		"DefaultDevice"
	Monitor		"DefaultMonitor"
EndSection

Run

Code:

hwinfo --gfxcard | grep -A2 solution

to see if the display reports preferred resolution, HorizSync and VertRefresh. If Hor. Sync Range is returned, replace the numbers in xorg.conf with them (if they differ). Next, reboot with only the HP connected via DVI to see if it lights up when the GUI login greeter is due. If not, try changing xorg.conf to use the VertRefresh returned by hwinfo, and try another reboot.

I tested this very file with a (normally working, 2003 manufactured) Dell 17" 1280x1024. It works without producing any error messages I could find in dmesg, journalctl, Xorg.0.log or .xsession-errors:

Code:

# inxi -GxxS
System:    Host: big31 Kernel: 4.12.14-lp151.24-default x86_64 bits: 64 compiler: gcc v: 7.4.0 Desktop: Trinity R14.0.6
           tk: Qt 3.5.0 wm: Twin dm: startx Distro: openSUSE Leap 15.1
Graphics:  Device-1: Advanced Micro Devices [AMD/ATI] Oland [Radeon HD 8570 / R7 240/340 OEM] vendor: Dell driver: amdgpu
           v: kernel bus ID: 01:00.0 chip ID: 1002:6611
           Display: server: X.Org 1.20.3 driver: amdgpu unloaded: fbdev,modesetting,vesa alternate: ati
           resolution: 1920x1200~60Hz, 1280x1024~60Hz
           OpenGL: renderer: AMD Radeon HD 8500 Series (OLAND DRM 3.27.0 4.12.14-lp151.24-default LLVM 7.0.1)
           v: 4.5 Mesa 18.3.2 direct render: Yes
# xrandr
Screen 0: minimum 320 x 200, current 1920 x 1200, maximum 16384 x 16384
DisplayPort-0 connected primary 1920x1200+0+0 (normal left inverted right x axis y axis) 519mm x 324mm
   1280x1024     60.02 +
   1920x1200     59.95*+
   1920x1080     60.00    59.94
   1680x1050     59.95
   1400x1050     59.98
   1440x900      59.89
   1280x960      60.00
   1280x800      59.81...
DVI-I-0 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 338mm x 270mm
   1280x1024     60.02*+  75.02
   1152x864      75.00
   1024x768      75.03    60.00...

I'm running low on ideas, other than opening it up to inspect its caps. One I've never tried remains, uploading an edid.bin file, discussed among other places, here.

emacsomancer · 05-20-2019, 11:14 AM

Quote:

Originally Posted by mrmazda

Until such time as the HP can be connected to some other DVI output to confirm it can work as expected, let's try to get it to light up in Xorg. First, save the following as /etc/X11/xorg.conf:
.....
Run

Code:

hwinfo --gfxcard | grep -A2 solution

to see if the display reports preferred resolution, HorizSync and VertRefresh.

Do I need to reboot after setting the xorg.conf file? I've tried doing it without rebooting, and

Code:

hwinfo --gfxcard | grep -A2 solution

produces no output.

mrmazda · 05-20-2019, 02:32 PM

Quote:

Originally Posted by emacsomancer

Do I need to reboot after setting the xorg.conf file? I've tried doing it without rebooting,

Reboot is not necessary, but restarting Xorg is.

Quote:

Code:

hwinfo --gfxcard | grep -A2 solution

produces no output.

I seriously botched that request. This is what it should have been:

Code:

hwinfo --monitor | grep -A2 "Max. Resolution"