For Quad-Channel RAM memory bandwidth you might want to consider a Ryzen Threadripper 2920X or 3960X CPU for AMD. Otherwise for Intel LGA2066 with Quad-Channel RAM support there is the i9-10920X CPU.
Install at least 32GB RAM better yet having 64GB.
For the GPU I wouldn’t waste time and money with a GTX 970. You can get a used GTX 1060 3GB or 6GB at very cheap prices which is faster than the 970. But buying a RTX 3060Ti or plain RTX 3060 would be the best bet as soon as it gets released.
SATA SSD would be enough for most tasks or you could get NVMe SSD. Anyway for maximum performance and reliability I would get a used hardware Adaptec/Microsemi RAID SAS controller that can be bought at cheap prices on eBay. A 71605 or 7805 model then you could add 4 , 6 or 8 500GB Sandisk SSD and you could configure them with RAID-5 or RAID-6 protection.
Also ensure to buy a good UPS like the APC ones.