most programs are low on CPU usage when modeling, and so on. Most pre-render duties are single threading of some sort. Hence, a fast dual is better than a slow quad. Except for some heavy duty tasks, like rendering and - in poser - dynamic cloth calculations to some extent. Then those packs fully utilize whatever you give them.
And ... for most hobbyists, rendering can quite well take place overnight, which makes it useless to speed it up.

Unless you start doing pro work, large scale (say 7000x5000) photoreal imaging, or animation. Or large scale HD video work.

This is why modern intel i7-9xx have auto-overclocking onboard when only one CPU is utilized, this way you have best of both worlds. Your preview while modeling is handled by your video-card BTW. Either in OpenGL, but in some cases even by the GPU like the nVidia CUDA pipeline. I'm not that familiar with AMD and with video ATI-cards, but recent tests are quite promising: The test shown here don’t say all, but what they tell is that ATI FirePro’s deliver 150% of the speed at 2/3 of the price from nVidia Quattro, or better. (3DWolrd 136, review on my website).

A general pitfall in all this is that people are inpatient. Change a light, rerender. Change a material, rerender. It's like recompiling code every three lines. When you work this way, you need a lot of render-work, like the above mentioned pro/animation case. Then, you have a higher need for more CPU capacity. If you don't have the capacity, and choose a adjusted workflow, you might be even more efficient.

All the best.

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Usually I'm wrong. But to be effective and efficient, I don't need to be correct or accurate.

visit www.aRtBeeWeb.nl (works) or Missing Manuals (tutorials & reviews) - both need an update though