Could you fix it? Or is it something for the McNeel team since the Rhino frame buffer seams to cause the problem? Could it be possible to direct render to disk? Could save VRAM.
This looks like a Rhino issue. Regarding rendering direct to disk, this would be way too slow. A variant of this is happening in Octane 3, where you can save your render progress at a certain point to disk and resume at a later date. Also, memory management has changed in Octane 3, so the render buffers are now in CPU RAM rather than VRAM.