2018 Macbook Air hot/slow when using UHD monitor So I upgraded from a 1080p 27 inch monitor to the following

Samsung 32" UHD 4K Monitor
Model: LU32J590UQNXZA

I've tried connecting over HDMI using a USB C dock, and over Displayport with a Displayport to USB C cable.

In both cases if I'm doing anything graphic intensive, or even in a video call, my laptop gets hot quickly and starts stuttering to the point of the mouse and keyboard hesitating.

All I've read says the new macbook air should be able to handle a 4K monitor.  I mostly needed more screen real estate, not so much high resolution.

Am I expecting too much of integrated graphics?  I'm not expecting to game on this laptop, but video calls become non-functional, and when I'm using Affinity Photo it also starts screeching to a halt even when working on small images.
I have the same problem with my 2018 15" Macbook Pro. The only thing that helps is  to set the scaling for the display not to the max screen real estate.

It's not getting warm or anything, but the interface is kind of laggy.