Dreaded pink texture but ONLY in material view

I’m applying two textures together using a Geometry/SeperateXYZ/ColorRamp node combo. Both textures work fine before I apply the factor to the mixer. As soon as I connect the factor my material turns the dreaded pink, but only in Material Viewport. It shows up fine in Render Viewport. The only way it will show up in Material preview is if I disconnect the displacement. Please help!

Screenshots:

hmmm, how big are those textures? also what is your GPU?

I see that you are loading 9 separate textures, I was wondering if it was running over some internal buffer limit of 8 textures per shader, but I couldn’t reproduce this effect on my machine.

Textures aren’t overly large. downloaded from CC0, 2K Jpgs.

I’m running on a 2019 iMac, Radeon Pro 570X 4 GB graphics card.

Amd gpus tend to have all manner of weird issues. Plus mac is also a source of glitching.

My guess is a hardware/driver problem