[RESPONDED] Graphical defects (occasional)

Framework Laptop 13 Linux
1

The issue

I’ve been seeing graphical defects on my screen recently. I’m not sure if it started suddenly or if I just didn’t notice it at first by coincidence (see later on suspected cause). The graphical defects manifest in two ways: rainbow (but mainly green) snow (as in, maybe 1-5% of pixels on the screen show the wrong color, generally green or white but maybe other colors too); and full screen flickering blackouts (entire screen flickers out and then back, rapidly – like if you add and remove external monitors and the graphics reconfigures, except many times per second).

Suspected cause

I believe WiFi is the cause. Specifically, I think that WiFi traffic is the direct cause. I’m not sure if it’s a software issue or if there’s some physical electromagnetic interference which disrupts the graphics output somehow. I believe it’s software, though – more on that later.

The reason I suspect WiFi is that the glitches occur when there’s network traffic (not simply connectivity). As I’ve typed this, I haven’t seen a single defect. But when I start an ssh session, there’s a big surge in flickering; and then when I type each character into the ssh session, there’s a very brief flicker, or just a few seconds of snow. It correlates with joining WiFi networks, searching for WiFi networks, and net browsing (loading a website causes a big surge).

It seems to correlate more with 2.4G WiFi than 5G WiFi. When I first got my laptop, I was at home with a solid 5G connection. In the last week, though, I’ve found myself using more 2.4G networks and also have experienced this surge in graphical defects.

What I’ve done

I’ve run updates on all firmware. fwupdmgr upgrades and all. Everything is up to date.

Weird coincidences

I installed Ubuntu on a MacBook Pro back in college and saw a very similar thing. It would flicker in exactly the same way, though I never saw any “snow”. That’s when I first formed my WiFi hypothesis, and the correlation has held up with my Framework. Since the two devices have very different physical hardware, I think it’s safe to assume that the issue is software and not hardware.

Specs

I’m running Fedora 40 on the Framework 13 AMD 7040. Linux kernel 6.8.10-300.fc40.x86_64. If any other features seem relevant, please let me know and I’ll update with them.

2

Hi @Andrew_Wells1 , welcome to the community.

can you check if graphical glitch goes away, if you allocate more ram to the igpu?

cheers!

3

@Loell_Framework thanks for the suggestion! I’ve switched to Gaming mode (2GB RAM) for the iGPU. I’ll update back if it happens again, or after a while if it doesn’t.

Do you have any thoughts about why WiFi traffic might correlate with the glitches with reduced iGPU RAM allocations, or is the RAM allocation more of a general suggestion when dealing with graphics glitches?

4

@Loell_Framework Today I went to Starbucks with WiFi disabled. I’d been working on my laptop at home with a 5G connection and on the go with WiFi off. I turned WiFi on and immediately the screen glitched (flashed with black and white bands, then green snow).

A short while later, I enabled WiFi (without a glitch) and joined a network. The captive portal opened with a visual glitch. I clicked “Accept Terms” after which there was a series of glitches.

I don’t believe the increased RAM for the iGPU has had an effect, and I continue to suspect that WiFi is the trigger for whatever issue I’ve encountered. Looking forward to hearing any and all suggestions, for either diagnosing or fixing!

5

Hi @Andrew_Wells1 ,
would you be able to take a video of the issue? first time to hear wifi affecting graphical display.

6

@Loell_Framework Of course, see attached.

I performed the same test (toggling WiFi) a few days ago but did screen recording instead of using my phone (built-in Gnome screen capture). The captured graphical glitch did not show up in the recording, which I believe proves the issue has to be hardware (not software)… but I’m not 100% sure.

Video upload isn’t possible on this site so I uploaded my first YouTube video – I should perhaps have edited out my dishwasher noises, volume off recommended lol: https://youtube.com/shorts/1uwaDSe-qOo?feature=share

What the video shows is probably a 7/10 in terms of badness, relative to the types of glitches I have seen. 10/10 means the screen is actually unusable (totally black 95 to 100% of the time, for multiple seconds or longer) but that doesn’t happen too often. 4/10 to 7/10 badness are the most common glitches. involving the black flickering covering some portion of the screen. These briefly make the screen somewhat unusable, but pass quickly. And then there’s 1/10 which is the “green snow”. You can see a bit of it in the video if you look closely. Occasionally it shows up on its own, without flickering / blank screen, which aside from being what the screen is supposed to display, had no negative impact on usability.

7

This could be a good indication that the problem is the display.

can you check if flickering display is also present with this wifi commands disable/enable?

nmcli radio wifi off
nmcli radio wifi on

8

Wow, fascinating find – by using the provided commands for enabling and disabling the radio, I was able to produce (3 to 4 times in a row) the rarest form of the defect, the green snow (as the radio turned back on). It didn’t flicker, but I wonder if another time or in another circumstance it might flicker as well. I’ll try again later, but for now I think the answer is a pretty definitive “yes” that the commands provided are able to trigger the issue.

UPDATE, 1 day later: Tried again toggling the WiFi radio with the provided commands and got a really big flicker. Nearly the full screen went dark, briefly. Repeated this for the same result, thrice.

9

Can you check if distance from wifi router has something to do with it? like the one they are talking here?

Also have you tried reseating the display cable? I think step 1 to 5 applies from this guide then just replug the display cable.

10

Apologies for the delay, I was out of town. I reseated the display cable without any change. Also, I’m quite close to my router when experiencing these graphical glitches (though it’s possible it gets worse further away). It’s hard to measure quantitatively, though.

I tried briefly to lower the transmit power on the WiFi card without any observable success, but I’m also not sure how to validate that my changes took effect. If you have any suggestions for how to do that in Fedora Linux, please feel free to share them.

11

@Loell_Framework today I was inspired to do another internet search and have found an interesting trove of info. This thread is a near-perfect match for the weird coincidence I mentioned in my original post. Incredibly, the conclusions match what I’ve suspected for years (since my old MacBook, and continuing to my new Framework): that the frequency and throughput of the WiFi plays a causal role in the flickering.

The thread is linked from this redit in which a more recent comment mentions a WiFi 6 card causing them problems. I note that the AMD Framework comes with a WiFi 6 card.

This leaves me with a few questions:

  • does the display share a power line with the WiFi card?
  • is there a list of recommended compatible WiFi cards for the AMD Framework mainboard (in case I wanted to try a different card and see if that fixes the issue)?
  • do you have any further ideas for me to try after reading the musings / thoughts of those two posts?

Thanks!