It goes without saying, but have you run Lenovo Updates to make sure you have everything up to date, including as the bot said, the graphics drivers? It could be something that simple I suppose.I have a Lenovo Thinkpad T490, with 8GB Ram soldered and another 32GB chip added, both Samsung 2400Mhz. It usually happens when I'm using Zoom.
It should work but its possible Zoom is using more resources it did when the UHD Graphics 620/Intel 8th/9th gen came out and its hitting a roadblock somewhere.That's where I have trouble understanding the problem. The integrated card is an Intel UHD Graphics 620, my laptop also has a NVIDIA GeForce MX250 plugged in out of the box. Together they should have about 3GB of memory, shouldn't that be enough to manage a few windows plus screensharing?
It should work but its possible Zoom is using more resources it did when the UHD Graphics 620/Intel 8th/9th gen came out and its hitting a roadblock somewhere.
Not sure if this will work but you could try:
Resolving Intel Iris Integrated Graphics issues
Due to technical limitations with Intel Iris Integrated Graphics graphics, users may experience crashes or system freezes when trying to share their screen with the Zoom desktop client. To resolve ...support.zoom.us
Go to Settings -> Video -> Advanced Settings -> Video Rendering Method -> Switch from Auto to Direct3D9