Zephyrus M16 graphics artifacts when using on performance mode and above; GPU problem? Fixable?

[GhostPigeon]

Hi guys. I've got a Zephyrus M16 with the rtx 4070 laptop gpu and intel i9 13900H cpu. I'm experiencing some seriously major graphical issues when using the "performance" and "turbo" profiles in armoury crate, and when even on silent mode with the gpu set to ultimate. 

Some key points I want to make known up front:

• laptop was purchased secondhand, so warranty work is probably out of the question
• problem occurs on some games, but not all. Arma 3, Titanfall 2, Gmod, Bodycam and Fortnite experience that issue, but games like MFS2020 and Minecraft RTX don't have that same issue that I've seen when played on performance mode. 
• when the problem occurs, the glitching most often will bleed onto other programs, but occasionally won't
• members of my discord chat report that they can see the issue when im streaming my screen
• problem occurs on multiple displays
• ran 3DMark stress tests, GPU and CPU performed normal and without the above problem on performance setting

temperatures do not seem to be extreme, and the problem can occur when the gpu isnt under peak load, and then NOT occur when it IS under peak load.

I haven't taken the laptop to anybody to diagnose it but I'm hoping somebody here might have answers. Any ideas?

[GhostPigeon]

I haven’t done any of that yet but I have an update: I tried using the laptop in performance mode at another house and didn’t experience issues. I am going to test it further, but I think I may have dirty power at home. I’m waiting on a new laptop PSU to arrive to see if the one I have is problematic. I will try your suggestions if it turns out the electricity and PSU aren’t the problem and leave an update. Thanks for the suggestions. 

[GhostPigeon · Accepted solution]

So at this point here is the conclusion I’ve come to: something between the power supply and the laptop is going wrong. I have a new power supply and for a while nothing happened but recently after playing Microsoft flight simulator 2020 for roughly an hour it occurred again. At that time I noticed the power supply was really hot. And the artifacting  still does not take place when the laptop is unplugged. Therefore to me it only makes sense to me that something is wrong with either my electricity, the power supplies for these laptops, or something in my laptop between the battery and the power supply interface. I truly am at a loss, but I’m happy to know I can enjoy my games the way they’re meant to be, even if I can only do so with the laptop unplugged. I attempted to run DDU but couldn’t do so in safe mode due to windows being stupid and not letting me into safe mode regardless of what I do. At this point I will probably just take in to a service shop when I can. Thank you for the suggestions, and hopefully other users find my experience helpful.