[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: LXDE Display Coordination

ray composed on 2015-11-07 19:29 (UTC-0800):

> Felix composed...

>> That "somewhere" looks to be e.g.
>> /etc/X11/Xsession.d/my1920x1080toOverride3840x2160Xsetup in Wheezy or Betsy.

>> Before you try that, I fail to notice evidence you tried my 2015-11-01 22:11
>> -0500 thread suggestion to append the video mode you want X to use to your
>> kernel cmdline. Why not try that first if you didn't already?

>> 	video=1920x1080@60

>> You can do that on the fly by editing in your default grub menu stanza at
>> boot time. If it works, make an appropriate change to
>> GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub, then run update-grub and reboot.

> I was not able to find out how to add a parameter during the boot process.  

Your boot time Grub menu should say so, at the bottom, "e" to edit the
commands before booting.

> I put the video=1920x1080@60 in the 'default' line, update-grub, update-grub2 and rebooted.  There was no change.  

To ensure what you did happened without errors, upload the latest Xorg.0.log
to http://paste.debian.net/ so we can be sure, and look for other clues.

> Followup for previous typo:
> While the shell command had the correct designation '1920', I found file names using '1960'.  I changed all of them and rebooted, no change.  

> Also have:
> ~/.config/autostart# cat lxrandr-autostart.desktop
> [Desktop Entry]
> Type=Application
> Name=LXRandR autostart
> Comment=Start xrandr with settings done in LXRandR
> Exec=sh -c 'xrandr --output eDP1 --mode 1920x1080'
> OnlyShowIn=LXDE

For the time being, rename this file so it won't affect what we are trying to
do otherwise.

> During a Xfce session, I changed the DPI from 96 to 300 and did not observe any difference in the display.  I am wondering if my expectations are misaligned.  Reading Xfce 'How toos', I see many descriptions where people build a disktop widget to click to change settings as if they have not implemented an automated method - which I prefer.

Traditional xorg.conf and xrandr commands should be able to work as always.
Let's not mix up trying to use them with trying to get your DE to do them
(which amounts to overriding if working as designed). IOW, don't change
multiple things at once and expect to know why whatever is or isn't happening
is or isn't happening.

You started trying to use xrandr, so let's stick with xrandr methodology
until we either find it can't work, or get it to work - but only after we've
finished determining whether the kernel cmdline methodology could work for you.

I just tried here to get 1440x900 used by Xorg via kernel cmdline on a
1680x1050 display, and it looks like the Betsy and Wheezy 3.16 kernels may
not always be passing the cmdline video= mode to Xorg 1.16.4 (Betsy) or
1.12.4 (Wheezy) as is done with other recent kernels and/or X server
versions. It does work as I expect with openSUSE 13.2's kernel 3.16.7 and X
server 1.16.1. All of these using VGA connections, not DP.

When I did switched from the native 1680x1050 screen to a native 1920x1080
(HDTV) screen, and DVI port PC out to HDMI TV in,

	xrandr --dpi 108 --output HDMI1 --mode 1280x720

in /etc/X11/Xsession.d/95setup produced the desired 1280x720 mode. So, if
putting video=1920x1080@60 on kernel cmdline ultimately is not working for
you, try putting:

	xrandr --output eDP1 --mode 1920x1080

in /etc/X11/Xsession.d/95setup (with ~/.config/autostart hidden, removed or
otherwise not available).

As 3840x2160 is usually only supported by the Intel gfxchips' DP outputs, and
their VGA and/or DVI ports are limited to 1920x1200, you could try connecting
with a cable other than DisplayPort to produce the lower than native
resolution you want automatically without any need for software configuration.

Exactly which distro are you using?
"The wise are known for their understanding, and pleasant
words are persuasive." Proverbs 16:21 (New Living Translation)

 Team OS/2 ** Reg. Linux User #211409 ** a11y rocks!

Felix Miata  ***  http://fm.no-ip.com/

Reply to: