Building a Super PC for After Effects

Hi,

I've been doing a lot of graphic motion type of animation and have noticed my current PC simply cannot handle the demands. The BIGGEST problem is that it takes forever to pre-render a scene I want to preview after making edits... I have a budget of about $7-8k to build a pc tower just for AE, what would you guys recommend in terms of the best cpu, gpu, ram, storage, etcetc on the market?

I've heard that the i7-8700K is the best CPU for AE because it has the highest single core clock speed @ a possible 4.7Ghz. Would you recommend something else?

For the GPU, they say it helps to a certain extent, but the difference within the high end GPUs do not make a significant increase. (Currently have a GTX 980 but is it worth upgrading any higher?)

I plan on running at least 2 SSD M.2's and a HDD.

For RAM, I was thinking of running anywhere between 64GB - 128GB @ DDR4 (4000 Mhz)

The only problem about running the I7-8700K is that the motherboards generally support only 64 GB of RAM. The kind of work I do in AE is very intensive for the PC to handle, would 64GB be enough? Or should I get a different CPU (+ Motherboard) so that I can have the potential for higher RAM capacity but lowering the CPU's full potential? Which one do you think is more important for faster pre-render speeds?

I've heard that AE CC 2015 or newer will no longer utilize multiprocessing, thus making most Cores in your CPU useless. Am I better off using the older versions of AE (ie., CC 2014) so that I can utilize multiprocessing and take advantage of my other cores? Would this give me performance gains? I know I'll miss out on some features but if it makes my pre-rendering speeds faster, it would be worth it.

I'd love to hear your opinions on a SUPER PC Build for After Effects.

Cheers