System specs don't seem to have effect on laggy viewport? Why isn't Rhino utilizing available resources?

Hello, I am running Rhino5 64 Bit.

I have a 137mb .3dm file that is very laggy in the viewport when certain layers are on. Obviously, these layers are the ones with the most data in them, but there aren’t any complex surfaces, just basic planes, and some curved surfaces.

I would understand that a computer with low specs could lag because it doesn’t have the required performance to handle the file. My gripe with Rhino is that, even though I have a very good system (that my firm paid a lot of money for), it doesn’t seem to make a difference in the viewport performance. In fact, I opened the same file on another, lower-spec computer, and got pretty much the same results (similar FPS). What’s even weirder is that, if I increase the OpenGL appearance settings, there is still barely any difference, because my graphics card can handle the 8x anti-aliasing with ease. But there is not much difference in FPS.

This leads me to believe this is a software problem. If you watch my video, you can see that my RAM and GPU is barely being used, even though I have a lot of excess resources available. I am OK with Rhino using more RAM and increasing GPU usage, even up to %100, if it means I can get better FPS in the viewport. But it doesn’t seem to want to do it. I don’t know if I’m doing something wrong, or if I’m correct in my assumption that this has to do with Rhino itself.

I would appreciate any comments on the matter.

Note: I have updated to the latest driver for my GPU and all other drivers are also up-to-date. I get better performance in wire frame mode, yes, but the FPS is still too low. Notice when I begin rotating the model around, CPU utilization jumps to mid 20’s, while GPU utilization increases 2% at most.

Hello - how many objects are on/displaying when it slows down? (Ctrl-A will print out the number of objects selected).


Ctrl+A gave me this:

15 extrusions, 2 hatches, 1 point, 4711 curves, 572 polysurfaces, 27997 surfaces, 2 meshes, 18 text added to selection.

I realize and understand that this is a lot of geometry to be manipulating around. The culprit is actually one layer which has 27.340 surfaces by itself, things flow smoothly when I turn this layer off.

What I don’t understand is why a significant increase in GPU power results in a marginal increase in viewport FPS. My computer is a beast compared to the other computers in the office, but the file behaves similarly on the other computers as well.

You may want to test that with v6.

I agree with nathan that you should try it out in v6. The reason the GPU isn’t doing much in this case is because the display is bottlenecked by the CPU due to the amount of objects in the file.

If the file is still very slow in v6 and you’d like us to take a look then please attach the file or send it to us via