intel uhd 630 graphics not working in uhd resolution

[alenist]

Hi, my desktop computer is equipped with an integrated graphics card Intel uhd 630. I just bought an Optoma UHD40 projector capable of 4096 or 3840 x 2160. I connected it through HDMI. The projector and the cable work well with a laptop running windows 10. Unfortunately, when I select the higher resolutions in Debian Buster Kde, the projector says that it is searching (for signal), but the search never ends. Please note that it doesn't say "No signal", but "Searching".
What to do?
Thanks
Alessandro

[Head_on_a_Stick]

Have you installed the firmware?

[alenist]

I have firmware-linx-free and firmware-misc-nonfree installed. Do I need something else?

[Head_on_a_Stick]

You should probably install the intel-microcode package as well but I wouldn't think that is a factor for this particular problem.

Is anything printed to the systemd journal or ~/.xsession-errors when it's "searching"?

You could try forcing the Intel DDX driver: https://wiki.archlinux.org/index.php/In ... figuration

No idea if that would work though, I have no experience with external displays.

[alenist]

The Microcode is installed. I looked in dmesg and I found this, which seems relevant:

[drm:intel_enable_ddi [i915]] *ERROR* [CONNECTOR:86:HDMI-A-1] Failed to configure sink scrambling/TMDS bit clock ratio


but I have no idea what it means.

The Arch page says

"For the DDX driver (which provides 2D acceleration in Xorg), install the xf86-video-intel package. (Often not recommended, see note below.)"
I re-installed that package, but nothing changed. Should I do something else to force ddx?

in xsession-errors I couldn't find anything relevant,.

[Head_on_a_Stick]

Should I do something else to force ddx?

First check the X.Org log file to see if the Intel or modesetting driver is being used. If modesetting is loaded automatically then create the X.Org configuration file listed on my linked ArchWiki page to force the Intel version instead.

I am presuming here that you're not using the Wayland session for Plasma.

[alenist]

It was using modesetting. I created the Xorg.conf file and now it uses the intel driver, but still it is not working at higher resolution. And I got the same error about "sink scrambling".

[Head_on_a_Stick]

Try booting with this kernel command line parameter:

Code: Select all

i915.enable_guc=2

Reference: https://wiki.archlinux.org/index.php/In ... re_loading

[alenist]

I booted with that option and Igot the following lines in dmesg:

sudo dmesg | grep GuC
[ 1.420002] [drm] GuC communication enabled
[ 1.431958] i915 0000:00:02.0: GuC firmware i915/kbl_guc_33.0.0.bin version 33.0 submission:disabled

[alenist]

I changed the cable with a cheaper one, and now everything works fine
Thanks, and sorry for bothering you with stupid question.

[arzgi]

I changed the cable with a cheaper one, and now everything works fine
Thanks, and sorry for bothering you with stupid question.

Great! Can you please add [SOLVED] to the front of the header in your first post in the thread.