Laptop display cannot show red, HDMI output can, VGA too, so looks like hardware issue, but is a malicious video firmware mod a possibility?
 

Suddenly a laptop lost the ability to show pure red pixels properly, they appear black, and pure green appears yellow. This does not occur on external displays via HDMI or VGA. Probably a hardware fault of the laptop display then. But could you please consider and help investigate another possibility:

The laptop has two GPU's. What if one GPU has had its video firmware messed up maliciously during Windows boots, and the other has not? Can we swap them over and make the external display show faulty pixels and the laptop display work correctly?

Specs:

https://www.gigabyte.com/Laptop/P35W-v3/sp#sp

More likely the cable to the screen got damaged. If it is still under warranty give them a call.
Lots of firmware gets reloaded during each boot, so your described scenario is not likely.

Thing is, this is an expensive laptop and the cable change will probably cost an arm and a leg. Is it too hard to redirect the alternative GPU output to the internal display from the command line and see what happens?

Not to mention shipping can take way too long and the laptop may be stolen in riots.

Not only hard, but impossible. Your choices are:

• Use it as is
• Get it fixed
• Buy a new one

This is a hardware issue; there is no 'malicious firmware' involved.
What are you even talking about??? What riots? The only delays any shipping company is alerting folks to, are those due to covid. If you're saying that an attacker put malicious firmware on your system (for no apparent reason) just to mess with the color on the screen, and are concerned with rioters stealing things...not sure what anyone here can help you with.

I was talking about political riots.

How do I find out which of the two GPU's is currently used?

Again, which ones??? I've heard about DEMONSTRATIONS, but not RIOTS, and certainly zero that affects shipping. You seem to be very misinformed.
Doesn't matter in this case; again, either the cable is loose or bad. It is a hardware issue...either fix the hardware or live with it.

I have no energy showing you videos of shops being looted (as in, getting empty) and burnt (as in, fire turns everything to ashes) including an incident where a shipping company's van is being looted. This is not a political forum so let's talk about TECHNICAL issues please. Two GPU's, each with its own display, is the way it works? Yes or not? Most laptops have one GPU and can still display different graphics on different displays simultaneously. I think I am only using one GPU in this laptop too, with two outputs, one external, one internal, and the other GPU is dormant but can be activated. How do you control which GPU is active?

Even 5 years ago one should fully investigate software issues and workarounds before sending off a laptop to a repair shop.

So then why did you bring up these (apparently) massive 'riots'? Sorry, but no. Again, you are either getting your 'news' from dubious sources, or are conflating it quite a bit. Either way, you're wrong.
And **AGAIN** it does not matter. On a laptop, there is ONE SCREEN with ONE CABLE/INPUT...PERIOD. If that cable is loose/bad, you can switch between 15 video cards, and the output will remain as it is.
Then please do so; nothing you've said indicates anything but a hardware issue.

You think one GPU is permanently connected to the internal display and the other GPU is permanently connected to the HDMI port, right? Then what do you think this is?

https://www.linuxquestions.org/quest...1&d=1605554794

Because I thought everybody literate enough for this forum is not getting their news from TV only and has therefore seen such videos - they are all over the place.

From the help on the nvidia control panel:

https://www.nvidia.com/content/Contr...reference).htm

The nvidia GPU in this laptop probably drives both displays while the integrated graphics processor only ever drives the internal display if anything, and the latter decision is made in software, not hardware.

Now I cannot see any difference in Windows when the nvidia GPU is deselected. What's the proper way to test with frames per second or something to confirm the slower GPU is being used, in linux or windows? In the hope that the path from the nvidia GPU to the internal display is damaged physically or software-wise while the path from the integrated graphics to the internal display is fine.

Exactly what it shows: the two video cards your laptop has. Now this is the part you need to pay attention to...those two video sources have external ports, which CAN work if chosen. What you **DO NOT HAVE** is the ability to do this with your laptop screen. AGAIN, since you're having trouble understanding this...you have ONE LAPTOP SCREEN with ONE CONNECTOR, PERIOD. You cannot somehow magically make that broken cable/display work through software. Either your display, display-driver hardware, or cable is going bad...you only have ONE OF THOSE EACH. Understand???
Well, you're posting here, so I'm guessing not. Good luck with your 'videos', and I'm sure they're showing the 'real news' (to you). If you're so fearful, get your packaged insured for full replacement value, and get it picked up at your home. You won't have to brave the 'riots' then, and if it's lost/stolen/burned, you'll get your money back. Problem solved.
..and the part bolded for emphasis is exactly what you've been told repeated. YES...it it physically damaged. And from your initial post, you claim that the EXTERNAL displays are fine, but internal is not. Now you're changing your story to be the integrated graphics to internal is fine??? Which is it??

Again: get your laptop repaired or replaced. Nothing else can be done to help you.

You still don't get it and too authoritarian to ever get it, the title says "looks like hardware issue", that means, the OP knows it's likely a hardware issue, only hoping to exhaust any workarounds if any exist and depending on the place in the signal path where the physical damage is, and that path has been proven to have a software aspect too (because without a software aspect you cannot select a GPU in the nvidia control panel).

Looking to TEST if the integrated graphics is fine or not, not that is fine. If it is fine, and the path from it to the display is fine, it will be selected and I will live with a slower laptop as opposed to a missing in action laptop.

Right...'authoritarian' to tell you what your problem is when you asked. Again: you can select whatever you want in the control panel...that DOES NOT change the laptop screen, does it? Try to spin it however you want...you have a hardware problem, period.

AGAIN: You have ONE SCREEN with ONE CONNECTOR. There is still no magic way to select something in software to make another cable/connector appear on your laptop screen and be used. If it doesn't work, but the external connections DO, that means the problem is hardware, not software. Either fix it or don't..your call; again, we can tell you things, but we can't understand them for you, or make you do them.
So go and do whatever 'test' you think you can do with a single connection/screen...there is, still, not one. Your only 'test' is to connect screens to the external adapter(s), and see if they work. If so..your video hardware (both of them) are working. And you now have proven (again) you have a hardware problem. You have one path to one screen...that's it.

Gosh, aren't you reading anything? The wanted test of the integrated graphics is with the internal display, not external displays - nvidia does not allow external displays with the integrated graphics as quoted from the nvidia site above.