Many people might already know this but I just realized it. I have 5 iPhones as NDI cameras. They come in as 4K inputs. I wanted to have a close-up of a subject within the 4K shot. At first, I set up a new NDI input and Zoomed in and positioned the frame to just view what I wanted to see. Each new NDI took a lot of GPU resources.

Then I realized that I could delete all of those extra NDI inputs and create new inputs that are multiviews with just one input source and then position the view to what I wanted in that multiview. Multiviews do not take up GPU resources. In total my GPU usage was cut in half and I could have a lot more HD views inputs within a 4K input than before.

It works very well