Slowing down

I’m new to Blender, and really to the world of 3d in general, and have a question about my computer. I’ve only made the one model using blender since i’ve only used it for approx. a week, and have already notice that my computer slows down to lag mode while modeling the one thing. Granted, i had about 3levels of Subdivision on it, i doubt it should be running as slow as it is. What are the main contributors of this slowness, if you can tell?

What are your computer specs? Graphics card?

If you add 3 subdiv levels, the total polycount goes up 64 times (in the worst case, the best is when the model is made of triangles, when it’s “only” 48 times, but it would look ugly). If your model has 1000polygons (you can see this in the right upper part of Blender’s window) after subsurfing it will have 64 000. And these must be stored in the graphics card memory and computed. Even worse, if you already applied it, while modelling this mesh needs much more RAM and CPU power.

So if this is visible in 3d view, your graphic card might have problems with it. So turn it off, or lower it.

On my lame desktop system I generally use subsurf level 2 for modeling, and use set smooth or autosmooth as well. The improvement between level 2 and level 3 is slight. You can always increase the render level to 3 to get the slightly smoother result, while not slowing down your modeling.

I generally don’t notice a lag until my scenes get very complex. With my two wip models (see my sig) there’s no lag at all.

Somewhere I’ve read, that Blender’s OpenGL implementation isn’t the fastest , but it is made more for compatibility with older hardware. This might be a problem when your scene is very huge and you have a high-end graphics card, but Blender cannot squeeze the power out of it. But from my experience, it runs well.

I use max. level 2 for displaying in 3d view, for rendering it doesn’t matter if there is enough RAM. But yes, the render time goes up, so level 3 enough. If the picture isn’t rendered in very high resolution, usually there aren’t enough pixels in image to show the extra dense geometry.