Which is right resolution for 2 monitors to keep on, Dell G5 15 5587?

@INTSSED  I prefer to avoid using scaling because as you say, sometimes you encounter problems. But 3840x2160 at 100% scaling on a 15” display would be completely impractical for me because that would make everything far too small to be comfortable. That’s why I specifically avoid 4K laptop displays and instead get 1080p. But if you have a 4K laptop display, then the “better” choice is whichever option gives you the best overall experience. There’s no universal answer.

Thanks for answer, jphughan! I am designer, also graphics designer, just bought to use like monitor with better resolution.

@INTSSED  Happy to help, and understood, but as you've found, some applications don't respond well to scaling, which can make using displays with a high pixel density somewhat problematic.  And using multiple scaling settings across multiple displays simultaneously presents drawbacks of its own, because in that case Windows will still only render at a single scale factor internally and then perform post-render GPU scaling to adjust the rendered content for the other scale factors in use.  As you might expect, that doesn't look as good as rendering for the target display's scale factor natively, that's how Windows works today.

Thanks for answer, heughan!
Actually that is not a problem, just annoying. I have changed laptop monitor resolution to 1080 :).
Now looks solved, will see. 

I'm worried about Thermal capabilities, there are discussion: Termal question Dell G5 15 5587?