I am an amateur game developer, and I've been reading a lot on how computer graphics rendering works lately. I was reading on the Z-buffer recently and I can't quite seem to be able to wrap my head around what exactly the Z-buffer looks like in terms of memory. It's described to contain depth information for each fragment that will be drawn on-screen, and that modern Z-buffers have 32-bits, so would that mean that on a, let's say, 1920x1080 screen it'd be just above 8MB (1920 1080 32) per frame?
I still don't quite understand what this value would be to a GPU (maybe it can crunch it easily), or if this value is even correct. Most demostrative implementations I found implement the Z-buffer as a simple array with size (height * width), so I'm basing myself off of that.