Question Bizarre issue with a laptop

[Alesaiko]

Hello. Some time ago I was playing a game when suddenly colorful dots all over the screen appeared.

GPU problem, you say? That's what I thought at first. But after a while I've discovered some really strange things:

1) Everything works perfect on a dedicated display, including dGPU and iGPU. Nothing is wrong there.

2) The existence of iGPU drivers (Intel UHD Graphics driver) removes any image on internal display. This is extremely weird.

3) There are artifacts during boot-up, during the Dell logo and in BIOS.

4) Windows boots in safe-mode (due to a lack of iGPU driver), but there is nothing on the screen in an ordinary mode, unless a dedicated display connected.

5) Some movement of an internal display was helping at first. Another weird thing.

The laptop I'm using is Dell G5 (i7-8750H + GTX 1060). As you can judge, there is nothing wrong with the CPU and both internal and dedicated graphics, but there is something weird with the internal display. I've never experienced this before.

I've already reconnected all connecters I'd found in a laptop, except the ones which are sealed in a display unit itself.

What is the root of a problem? How to fix it?

 

[boju]

If external monitor isn't showing the same symptoms it makes ya wonder it's either the screen or the wiring to the screen.

Briefly searched dell g5 screen replacement and there appears to be some useful videos for you to look at and investigate what's involved in replacing screen or possibly just the wire. May be able to have a pc store source the parts if you know what you need.

For testing, lean the screen back and forth like you were opening or closing the lid and see if doing that causes artifacts.

 

[Alesaiko]

If external monitor isn't showing the same symptoms it makes ya wonder it's either the screen or the wiring to the screen.

Briefly searched dell g5 screen replacement and there appears to be some useful videos for you to look at and investigate what's involved in replacing screen or possibly just the wire. May be able to have a pc store source the parts if you know what you need.

For testing, lean the screen back and forth like you were opening or closing the lid and see if doing that causes artifacts.

Yeah, this seems like a display issue, but there are a few weird things:

1) This started during the game, when I was not touching the display at all.

2) There is an image with colorful dots during boot-up and in BIOS.

3) There is no image in Manjaro and Windows, BUT, if I reload into safe-mode or manually remove Intel UHD Graphics driver, the image with artifacts will appear in the system.

4) Screen flex helped a bit at first. I've rebuilt the whole display module, but it doesn't help

 

[boju]

Number 1 had me think it could have been an eventual issue from heat or wiring rubbing somewhere.

Number 2 is odd, if it's consistent then that kind of blames the igpu doesn't it. Laptop's screen feed's off of the igpu and dgpu routes though this protocol.

Number 3 coincides with my thoughts about no 2.

How are you cpu temps?

 

[Alesaiko]

Number 1 had me think it could have been an eventual issue from heat or wiring rubbing somewhere.

Number 2 is odd, if it's consistent then that kind of blames the igpu doesn't it. Laptop's screen feed's off of the igpu and dgpu routes though this protocol.

Number 3 coincides with my thoughts about no 2.

How are you cpu temps?

I also thought that thermals caused the problem, but I use a high-performance thermal grease (Grizzly Kryonaut) along with mediocre undervolting with downclocking in ThrottleStop to extend the laptop's hardware lifespan (ironic), so my temps during the game were really low: 60-70°C on CPU and exactly 69°C on GPU.

When I use a dedicated display, I can utilize the iGPU. I've already tested it in games and Hashcat, where it showed itself pretty good, neither artifact not other issues detected (maybe it's because the image is rendered by UHD but showed by GTX as HDMI is connected directly to dGPU, but then Hashcat could at least report something) .

At first I thought that iGPU is the thing, but the fact that it works fluently when a dedicated display is used kinda makes me doubt.

Currently, I don't even have the glue what's going on. Never experienced such a thing before

 

[boju]

Me neither, its one problem after another contradicting each other lol. Maybe swap your hdd out with another and test a complete reinstall of Windows so you don't lose anything if it doesn't work.

Or try reinstall Intel igpu drivers from Intel's website and maybe do Nvidia as well just in case.

 

[boju]

But then again artifacts or coloured dots during bios or post has nothing to do with drivers as they aren't even loaded yet or even Windows. Argh!@

 

[Alesaiko]

But then again artifacts or coloured dots during bios or post has nothing to do with drivers as they aren't even loaded yet or even Windows. Argh!@

Yup, astonishing. Gonna bring this laptop to a local service centre. I will tell if they find anything.