Screen blanking with external monitor


#1

This is REALLY getting tiresome. I have a new Lenovo ThinkVision 27" monitor and I’ve connected my Librem13v4 to it with a high quality HDMI cable. The intermittent screen blanking is becoming a real pain in the ass, especially when I am using it for work. I have seen multiple complaints on here about this behavior yet no one has been able to find a solution. I would like to think the Purism folks are monitoring this forum because this really ought to be addressed if this product is to be taken seriously. I love the hardware and software. I get a nice 4K display on the monitor, but the blanking really is irritating.


#2

Hello @gdanko.

What did Purism told you when you contacted the support?


#3

What is your coreboot version? Please upgrade it and try again.


#4

BIOS Information
Vendor: coreboot
Version: 4.11-Purism-1

How do I upgrade it?


#5

Easiest to update for me was to use the utility that purism provides. Instruction and the scripts can be found here:
https://source.puri.sm/coreboot/utility

Also, more instructions and descriptions at:
https://puri.sm/coreboot/

(I think though you’re at the latest version already, but the coreboot utility should tell you that if true).


#6

I upgraded coreboot and it’s still the same issue.


#7

I’ve noticed the blanking often happens when the CPU fans speed up. For example, I use Dropbox selective sync and I added my “git” folder for work and when I added that folder, the fans sped up and the blanking was more frequent.


#8

Out of curiosity, does the screen blank when the laptop is not plugged into power? So far your description looks very similar to what I noticed on my system and don’t understand at all yet.


#9

Mine is always plugged in since I use it as a desktop replacement so I can’t tell you. I could try later today.


#10

@mladen You asked me in this post about the coreboot as well. Looks like @gdanko has the issue with the newest coreboot, myself with the newest PureBoot. Any ideas?

@gdanko I’d still be curious if the problem consists if you unplug the computer from the power supply and run on battery. A while a go I had a discussion with @kieran that this isse might be related to dirty mains in the house and I wouldn’t be surprised if that would be in fact the case (still weird that it only happens on the Librem). Anyway, I was wondering if there would any reason from the internal wiring why this could be? Just fishing here…


#11

Could you expound upon this. What exactly happens? For how long? Does it self recover? Does it follow any pattern, or seem totally random? Is it worse if there is nothing going on in the screen or if something like a video or some other app is running the screen? Does it happen the same when it start up, or does it appear after some usage? In other words, share with us a lot more about exactly what is happening.

Also do you have any ideas as to what could be causing it? Is it vibration or thermally related for example? If you put your system in the freezer and then take it out and run it is it better? (BTW, pay attention to condensation if you do this and if you live in an area with humidity. You don’t want to get your wiring wet. You can run it in your freezer, then put it in a sealed plastic bag until it warms back up and this should keep the moisture out of it.)

Thanks.


#12

ince it is an HDMI cable i’d like you to make sure that it’s properly connected at BOTH ends. i say that DisplayPort has those “aligator-fangs” that keep it more secured in place whie HDMI does not …

also make sure about the power cable being secured in place (not wigling or loose)


#13

The computer can be idle and it happens. It happens more when the computer is busy (compiling, etc).
The screen will go black for 2-3 seconds. There is no pattern to it at all. While the screen is blank I can still type and everything so it just seems to be the video signal. I don’t really know what could possibly cause it. I have a high quality cable and it’s plugged in snugly. I am tempted to boot off an ubuntu live installation and see what happens in ubuntu.

Also, my monitor has two HDMI ports and I’ve tried them both.


#14

I used to repair computers for a living. Quickest way to solve some of the problems is by swapping components. In this case swap out the external monitor, if you haven’t already, preferably with a different brand. Also test the monitor with some other feed. Swap out the cable too. And yes, swap out the OS, as you suggest. That is a good idea.


#15

I am seeing the same problem with Ubuntu 20.04
The issue exists with both my Philips monitor and my television
I tried multiple cables and made sure they are seated properly.
I am at a loss.


#16

? Ok, other ideas. Still good to try it very cold. Transistors work better cold, and when they fail they almost always fail as the temperature goes up. Also I would consider blowing it out with compressed air. And shaking it good. There could be some dirt somewhere in it. Also some devices fail under vibration. … Or like I said there could be an internal connector that is not fully seated, or is corroded. How is the humidity where you are an is there any corrosion? Here in Kauai we have lots of corrosion from the salt air.

What you have is an intermittent failure. That is a special class of failure, where it’s not totally broken. These are the hardest to fix, but the good news is that if you can figure out how to make it more or less, as you already have done w/ load, you might be able to trace it to what’s causing it. For example, if you mostly idle your box, does it ever still blank? And if you run something that maxes out your cpu cycles, like perhaps a full viral scan with clam, does it blank lots or much more? If so try it in the freezer, or soon after you take it out. If there is a big improvement from this then you have a bad chip somewhere. Sometimes one can take a can of freeze spray and spot freeze each chip one at a time and find the chip which is bad. Almost always the components that have issues are those with more power going thru them, starting with the power supply, and moving to the high speed cable driver chips. I would think is should be possible to get a mother board swap if you can determine that it’s the board. Also I would swap the power wall wort or whatever powers it.


#17

When you log in, try switching to X11 or Wayland, whichever one you’re not using.


#18

I have a similar problem with my work computer - it’s connected to a 4K TV, and the screen will spontaneously go black for a second or two and then come back. Sometimes it happens a few times a day, sometimes not at all, but usually at least once or twice. Any typing input during that time is accepted, so it appears to be purely a video issue. Here’s the interesting part: it’s a Lenovo laptop running Windows. I’ve also had the same problem with a MacBook Air (for work) hooked up to a 2560x1440 monitor. So I don’t think it’s a Purism-specific issue.

The only common element that I can think of: Intel graphics paired with larger-than-HD monitors.


#19

Then it’s not just me.


#20

It is absolutely not just you, I have suffered from this ever since I got my Librem 13 v4 last year and did raise this in a different thread. Given the hint that it could possibly be related to Intel HD Graphics and not just the Librem, I did just try the “best” cable I could find in the house, from a Nintendo Switch, but to no avail. I have spent far too many hours trying to fix this and I am still at a loss as to what the heck it could be. After giving up some time around October last year I had hoped it would be fixed with the new coreboot version, but sadly that does not seem to be the case.

In my case I have a Dell UltraSharp UP2516D running at 2560x1440@30Hz hooked up and I am currently running both the laptop screen and the external (not that it matters, the blanking is still there with or without the laptop screen running). It is strongly correlated with CPU usage and it is only ever the external screen that goes blank.