Compatible monitors

I’m looking at getting a pair of monitors and I was wondering what the Librem 5 and the other Librem computers support.

Should I get a monitor with USB-C 3.0?
Displayport 1.2?
Would daisy-chaining work with any of the hardware with DisplayPort 1.2 MST or USB-C?

What spec’s in monitors do you look for?


I could be wrong but I think there is no single interface that is mutually compatible as such i.e. Librem laptops are HDMI (1.x) only while, once it is widely available, the Librem 5 will be DisplayPort over USB-C only (a so called USB-C alt mode). So to get a monitor that can be used with either, you would need a monitor that specifically supports both of those.

However “Librem computers” could be more general than “Librem laptops”. Throw the Librem Mini into the mix and the situation changes again (as the Mini reportedly supports HDMI 2.x and DisplayPort and the specs don’t cover whether it will support DisplayPort over USB-C, so you would need to ask Purism if it is relevant to you).

Official answers are obtained by drilling through

Adapters could alter the situation further (with varying degrees of success).

So without more information, you should get a monitor that supports everything (HDMI 2.x and DisplayPort and DisplayPort over USB-C). Whether that suits your other requirements …

The main specs that I would look for are

  • interface
  • native resolution
  • screen diagonal

Depending on your use case you might also look for touch capability, color fidelity, other aspects of picture quality, sound support (connect speakers / built-in speakers / none), USB hub, physical rotate, …


and last but not least reviews, power-consumption, bit-depth, integrated speakers, integrated-usb-hub, cables in the box, supported color gamut, display-technology (IPS or VA or TNT or the more expensive QLED, OLED etc.)

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Thanks for the replies.

I borrowed a 23.8" WQHD monitor from work, but I like the pixel density on my 13.3" FHD laptop. The main issue with different pixel densities is that the text and content changes size between the two monitors.

So I would be looking at a 27" 4K monitor. This has nearly the same pixel density (163 PPI) as the 13" (166 PPI) screen.

Dual 4K monitors is only supported with DisplayPort 1.3 and higher. Could possible future revisions of the Librem13 laptop support 2x 4K displays through a port like USB-C?

PPI isn’t everything. You usually sit closer to a laptop screen than a separate monitor so then it’s more important. My 13" 1440p laptop feels like it has the same PPI as my 27" 2160p monitor but it’s in fact higher PPI on my laptop without me realizing it. For example, when Apple released the iPhone 4 and bragged about that you could not see the pixels, it was a tiny notice below that you could not see the pixels at 10 inches distance. Also notice how apples retina displays have different PPI depending on type of display, they don’t care about PPI but about “angular pixel density” which is a more fair way to calculate it.

My point of this is that 166ppi on a laptop does not look as crisp as 166ppi on a monitor due to you being further away from the monitor.

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See also discussion at and around: Re: librem-5-smartphone-final-specs-announced

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Yes, it is about how far away you are from the screen, that’s why I got the 24" QHD monitor to try.

Where I see the pixels are on the diagonals. If I sit straight I am 50cm from my laptop and 60cm from the monitor. Going through the calculations with θ = 2x10⁻⁴ and 5x10⁻⁴ radians from Rayleigh Criterion. I get the following table;

13.3" FHD  43 - 108 cm
23.8" QHD  58 - 146 cm
27.0" QHD  66 - 165 cm
27.0" 4K   44 - 110 cm

Below the range you’ll see pixels, between you may see pixels, and above the range, you will not see pixels. Then there is anti-aliasing and it is hard to provide qualitative information and that’s why I got a monitor to try. It’s a good monitor, it’s just I’m used to the smoothness on the 13" and flicking between the two monitors while working I notice the difference.

Even with two different ports, could the (future) Librem 13 drive two 4K displays?
It looks like the Intel HD Graphics 620 can support 4K @ 60Hz, so no, or can it do two 4K @ 24hz and the internal 1080p @ 24Hz? I’m not too sure how the GPU can vary the displays to fit within its bandwidth.

FYI: I have the Dell P2416D 23.8" and the equation is
monitor diagonal x [ sin(arctan(9/16)) / sin(1/4 π) tan(θ) ] / number of pixels on the vertical

hmm a fun idea … seeing as how the tiling WM in Pop!_OS already has a GNOME extension and can - ALREADY - be enabled in Ubuntu 20.04 LTS RC (today should be the day) …

what would be cooler ? having two 1080p monitors @ 24inch without tiling or one 1500R curved 2x1080p @ 49inch < with tiling enabled ?

I head about their tiling for Gnome, it’ll be very useful for a large screen. Trying to place windows to use the entire screen is annoying. One factor would be the price but I think the ultra wide display with tiling would be best.
(I never used tiling) If you can divide the screen into 5 segments and snap windows into the segments and then drag the boarder to snap the window into 1/2 a segment and then drag horizontally to cover 2 segments. That would be killer.

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well it’s only testing software so far but to me it looks good enough to inspire someone to install other WMs alongside GNOME and just play around with the other more powerful tilling WMs out there … distrotube does a good enough job of covering tiling WMs on lbry tv …

I’m also in the market for a new monitor and wanted to see if someone from Purism could give us a more definitive answer on this now that development has progressed significantly.

The requirement for a USB-C port on the monitor itself dramatically reduces the candidate pool of monitors and requires both compromising on specs and paying more just to have that port. It would also make the convergence aspect of the phone much less useful since most people probably don’t have a monitor with a USB-C port.

I’m assuming that the Librem 5 should be able to output displayport (and maybe HDMI) through a dock though. Something like what was demonstrated with the Pinephone:

So, can we plan to just use a dock?

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I don’t believe that is necessarily the requirement. A DisplayPort-over-USB-C to DisplayPort adapter (or to HDMI adapter) should work too if your monitor does not have a USB-C port. (And I agree your monitor most likely will not have a USB-C port. All but one of my monitors lacks a USB-C port.)

Also, you’ve quoted a reply that was answering a very specific question (What single monitor is compatible with all Purism products?) which is harder than the question that I think you are asking.

The good news is that in the four months since that reply, video out on the Librem 5 is reportedly working! So perhaps it is now possible to get more information about what monitor / adapter that particular person was using.

I’m sure that, once Evergreen ships, many customers will report successes (and failures) with video out. I know that I will test convergence even though I probably won’t use it much.

Latest indications are “no” for actually outputting HDMI but that doesn’t mean that you can’t connect the Librem 5 to a monitor that only has an HDMI port.

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Right, by “requirement” I just meant it as if we’re self-imposing this as a criterion.

From the Librem Social post about video out, I was thinking from @dos’s comment about how USB-C to HDMI adapters work (usually via DP alt mode) that we might be able to get HDMI output via a dock.

Dock or no dock, either way you are relying on an “adapter” if you have a monitor that only has an HDMI port.

In my experience with video adapters generally (nothing to do with the Librem 5), cheap-and-nasty adapters may have cut corners with the implementation, and compatibility can be hit and miss.

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