Horizontal sparks on the screen, caused by driver or a electrical fault?

Aknot · 2026-07-17T17:04:16+0100

I have some weird horizontal "noise" flickering on the screen, almost like sparks, can this be caused by the graphics driver? Best seen in the lower right corner.

Zoom

The VGA adapter is a AMD Radeon and I have tried TearFree true.

Radeon.conf is set to modesetting on pci0:1:5:0.

Thanks,

Maxnix · 2026-07-17T17:09:15+0100

Can't tell for sure, but wouldn't be surprised if it was the cable.

Aknot · 2026-07-17T17:12:19+0100

Maxnix said:
...wouldn't be surprised if it was the cable...

I actually read that this was common, but these sparks doesn't change at all, when moving the lid back and forth.
I have cleaned the connector with alcohol and a cotton swab too, just to be sure, no difference.

drhowarddrfine · 2026-07-17T17:25:14+0100

Tap and press at that spot to see if they change at all. If they do, it's the display.

kent_dorfman766 · 2026-07-17T17:31:32+0100

Historically those types of glitches are more often caused by driver/os issues.

Espionage724 · 2026-07-17T18:09:15+0100

Aknot said:
can this be caused by the graphics driver?

I've seen rare similar artifacting with Intel UHD 630; it'd show on some things like Thunar window parts like a black line or dotted. I do interesting Mesa envs globally and force Intel DDX and figure it's something with that

(seen it on Linux too Xfce/Intel DDX/no compositor)

Mostly guessing, but I would think AMD on Plasma 6 would do something different (Xfce no compositor + Intel DDX probably mixes 2D paths; AMDGPU and modern DEs are all-3D; while I've seen artifacting on Xfce stuff, I didn't see it in 3D games and wouldn't expect the same ordeal to affect AMD + Plasma 6 at desktop)

Do the artifacts disappear if you hover something over it? If on the desktop, what about dragging a selection box (like if going to select multiple desktop icons) over the spot?

Aknot · 2026-07-17T18:42:45+0100

Espionage724 I actually had to film this, and yes, they go away when moving a window pass the sparks

Never seen this before

Espionage724 · 2026-07-17T19:00:06+0100

I wonder how Plasma 6 renders the desktop background? I can't imagine it's repainting a static image at vsync or rendering it on GPU, but that almost looks like what's happening.

I'd try different desktop alternatives (iirc one was no icons/default, one with icons shown, and others like video wallpaper downloadable).

Aknot said:
Radeon.conf is set to modesetting on pci0:1:5:0.

I'd try amdgpu driver (pkg install something like xf86-video-amdgpu)