Cores x clockspeed.

The Intel 18-core is pretty pokey on clock speed. And the price....

The core i3/i5/i7 processors cannot run in parallel, i.e., you can't run two i7s on a motherboard. As far as I know, the same applies to the AMD processors (corrections very welcome). I would be especially interested if someone has dual Ryzens operational; that would have great potential, if Ryzens can run in parallel.

GPU rendering is good for ^some^ rendering tasks: portraiture, for example. But if you want to render a large enviro set with lots of geometry and complex materials, it will fail. GPU rendering is limited by the video cards' onboard VRAM. Also some render engines need AMD GPUs, but others need nVidia, so you have to choose.

The relatively cheap way to get rendering performance is to use a workstation/server motherboard and ^two^ Xeon processors. Used X5690s are about $140 each; each X5690 gives you 24 threads @ 3.46GHz (3.73GHz turbo). You'd need a motherboard with dual 1366 CPU sockets. While you might -at considerable cost- get a new processor which will outrun ^a^ X5690 Xeon, it isn't easy to outrun ^two^ X5690 Xeons.

RAM only affects the render in a pass/fail manner; if you have enough, the render succeeds, and if you don't have enough, the render fails.
So, installing lots of RAM is good, because it expands your capacity for larger scenes and larger buckets, but it doesn't speed the rendering.

Hard drive speed will have minimal effect on render speed.

If you want render speed, you want cores x clockspeed.

Poser 12, in feet.  

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