OK, we just replaced the graphics card in one of the workstations with a new NVIDIA RTX A4000 card, since that is listed in the Ansys installation guide and it's supposed to work for Mechanical APDL.  The problem is the same as before: I double-click on the Model line, it says "Starting Mechanical", it opens a new window, the GUI controls are shown, and the area that should show the model/arrows/ruler is black.  If I click on the + next to Geometry Imports, then click on Geometry Import (B3) under that, Mechanical crashes.