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I have a fairly simple scene - large ground plane, five uv spheres, Pro-Lighting envmap - that's consistently and almost instantaneously crashing Blender on render.
From my tests, it seems to be a result of a very high subdivision on my primary ground plane (which is approx. 2.8x7 blender units with around 54k verts), combined with a high subsurf level (for microdisplacement). It handles a
Level 3 Level 4 subsurf fine; crashes almost immediately at Level 5.
I've done a number of large scenes with millions of verts on this machine before (scene + 20k object particles, with randomly between 1500 and 17k verts each) and while it takes forever and an age to build, eventually it cranks through and renders just fine. I've had a few slow almost to a complete standstill for a while, but I've never had one crash outright.
I know someone is going to quote the subsurf exponent table to me, and I acknowledge that it's almost ridiculously high, but I do legitimately see a difference in the scene at that level.
Given that it crashes almost instantly, as soon as it attempts to synchronize that mesh object, is there a mathematical limit that it's hitting before memory even comes into play (this is a 16GB system)?
Is there some internal limitation to the number of vertices a scene can trigger via rendertime subsurf?