I join this post because I'm also looking at a new PC for simulations and render with Houdini. And it also creates the doubt that it is better to simulate above all.
I had in mind this PC:
Dell Precision T5610 Workstation with
CPU: 2x Intel Xeon E5-2670 v2 (10 core)
RAM memory: 128 GB
Graphic: NVIDIA GeForce GTX 1060 6GB
SSD: 256 GB SATA 2,5"
HDD: 2 TB SATA 3,5"
as you see?? Better than an i7??
Above all thinking about simulation and rendering. Although every time we go more to GPU rendering what interests me above all is that it is fluid in creating caches, simulations, etc.