Dual Monitors

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hyperion
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A rejoint: 06/17/2018

I just installed Trisquel yesterday. My two monitors are duplicating the display instead of extending as two separate displays. After trying to install the Linux proprietary driver for Radeon, it blackscreened on startup. Are there any libre graphics cards/Trisquel compatible Radeon drivers that can accomplish dual monitors? This is a deal-breaker for me.

Also: when it detects non-free software, is it always going to black screen? I would prefer it simply notify me and not let it install. When booting normally after the propriety driver install, it black-screened. When booting in upstart, I saw recursively looping messages saying something like "Free Firmware Required". I appreciate the blocking of proprietary stuff but I would prefer it not to require me to essentially reinstall the OS.

Thanks.

Magic Banana

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A rejoint: 07/24/2010

AMD is the worst for graphics. On the contrary Intel is the best. If you have an Intel processor with integrated graphics, you can physically remove the AMD video card: not only you would get dual monitor support but also better performances and a smaller energy consumption. With an AMD processor, older nVidia cards is what is best supported.

On the software side, you can always try a newer kernel (drivers are in the kernel) and see if the support has improved. Trisquel's repository has Linux 4.13. https://jxself.org/linux-libre/ has even newer versions.

chaosmonk

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A rejoint: 07/07/2017

> My two monitors are duplicating the
> display instead of extending as two separate displays.

Have you tried going to System -> Control Center -> Displays?

> Also: when it detects non-free software, is it always going to black screen?

No. Trisquel does not include proprietary software, but it does not impose restrictions on what you can install manually. I've seen installing the wrong graphics driver black screen Ubuntu upon startup as well.

> When booting
> in upstart, I saw recursively looping messages saying something like "Free
> Firmware Required".

Are you on Trisquel 7 on 8? Trisquel 8 should be using systemd, not upstart. When I was on Trisquel 7, I similarly got an endless stream of "free firmware not found" messages. The solution was to blacklist my computer's proprietary WiFi card.[1] In my case, the firmware was called iwl3945, which I got from the looping error message, so check the message (or post it here) to figure out what it is in your case. I had to do this every time I installed Trisquel 7, but it has not been an issue in Trisquel 8.

[1] https://trisquel.info/en/forum/trisquel-not-detecting-thinkpenguin-wifi-adapter-after-install#comment-118182

chaosmonk

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A rejoint: 07/07/2017

To clarify, I got the looping message upon installing Trisquel, without attempting to install any proprietary drivers. If this is the case for you then you should problably do the blacklist thing, as in my case those messages were logged and eventually filled up my disk space. However, if the message began appearing after installing the graphics driver, then the solution is to not install that particular graphics driver.

hyperion
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A rejoint: 06/17/2018

When going to Displays it only detects both monitors as one "Unknown" display. Pressing "Detect monitors" does nothing.

I'm using Trisquel 8. Once it black-screened I simply backed up my /home dir to my backup drive and reinstalled. So it's "solved" in the sense that I am currently using the OS again just fine, but the displays are still duplicating causing me to work with limited space. Do you recommend any graphics cards that don't require proprietary drivers and can dual monitor with Trisquel?

Edit: Yes, it only happened after trying to install the Radeon driver. I'd prefer no proprietary drivers -- I was just trying to make the displays extend.

chaosmonk

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A rejoint: 07/07/2017

> When going to Displays it only detects both monitors as one "Unknown"
> display. Pressing "Detect monitors" does nothing.

I don't have access to another monitor at the moment so I'm going from memory here, but I'm pretty sure that when I plug in a second monitor via VGA it says "Unknown VGA" so the fact that you see "Unknown" isn't necessarily a problem. Since it appears here, and since the monitor displays anything at all, it has already been detected, so it is not surprising that "Detect monitors" does nothing. Make sure that you have "Same image in all monitors" deselected, and then click on the monitor labled "Unknown" and make sure all the settings make sense. Sorry I can't be more specific without a way to try it myself.

You could also try running in a terminal

$ xrandr -q

to get information about all detected monitors, which might provide some clues. You might also try

$ xrandr --output XXX --auto --left-of YYY

Where XXX is the name of your second monitor and YYY is the name of your main monitor. The names will resemble something like VGA1 or LVDS and can be found in the output of 'xrandr -q'

hyperion
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A rejoint: 06/17/2018

"Same image in all monitors" is grayed out. I don't think the OS is detecting one of the monitors at all; it just thinks there is one monitor going. I attached what the interface looks like.

Here is the output of xrandr:

$ xrandr -q
xrandr: Failed to get size of gamma for output default
Screen 0: minimum 640 x 480, current 1920 x 1080, maximum 1920 x 1080
default connected primary 1920x1080+0+0 0mm x 0mm
1920x1080 0.00*
1280x1024 0.00
1280x960 0.00
1024x768 0.00
800x600 0.00
640x480 0.00

I'm probably going to have to buy a new card that doesn't use proprietary drivers.

monitors.png
chaosmonk

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A rejoint: 07/07/2017

> "Same image in all monitors" is grayed out. I don't think the OS is
> detecting one of the monitors at all; it just thinks there is one monitor
> going. I attached what the interface looks like.

I see. I thought you meant both monitors were showing up but onw was labled "unknown." I'm still a little surprised that you are getting anything in the second monitor. In my experience nothing has shown up on a second monitor at all until the system detects and I connect to it.

> I'm probably going to have to buy a new card that doesn't use proprietary
> drivers.

First I would try Magic Banana's suggestions. If you don't have Intel graphics, see if a newer version of the linux-libre kernel supports your graphics card. If not, h-node is a good resource for finding hardware that does not require proprietary software. https://h-node.org/videocards/catalogue/