This is one of those AutoCAD sneaky buggers that ended up killing a large portion of my day so I thought it worth sharing.
We do a lot of things to get the best performance with 3D models. I generate Oil and Gas processing plant models using CADWorx Plant Professional in AutoCAD. For the size of our projects, speed we have to work at, and drawing setup concurrent with model completion no other setup has been as effective as 3Dclip.
The problem I run into with 3DClip is that once my 3D model reaches a certain size I loose the visualization of my clipping boundaries. I can watch my viewport change as move the clipping plane but don't see a handy dandy line to show where exactly it is clipping.
Here's the fix I found. Options - System - Performance Settings - deselect wireframe display in the Degradation order section. Now if I could just get my front clipping plane to show up white, blue, yellow, or any color other than black given my black background! Anybody got any ideas there?