Got a PM from OP to help out and now i'm here.
The build posted by herrwizo is a good one, especially when you mainly use CPU render. Though, for rendering 2D/3D objects, GPU render is far faster than CPU render, up to 10 times. And due to this, i present a build that is optimized towards GPU render:
PCPartPicker part list /
Price breakdown by merchant
CPU: Intel - Core i9-9900K 3.6 GHz 8-Core Processor ($750.00 @ Amazon)
CPU Cooler: be quiet! - Dark Rock Pro 3 67.8 CFM Fluid Dynamic Bearing CPU Cooler ($88.58 @ OutletPC)
Motherboard: MSI - MAG Z390 TOMAHAWK ATX LGA1151 Motherboard ($156.07 @ Newegg)
Memory: Corsair - Vengeance LPX 32 GB (2 x 16 GB) DDR4-3000 Memory ($263.99 @ Newegg)
Storage: Samsung - 970 Evo 500 GB M.2-2280 Solid State Drive ($116.99 @ Amazon)
Storage: Hitachi - Deskstar NAS 4 TB 3.5" 7200RPM Internal Hard Drive ($127.77 @ Newegg Business)
Video Card: Zotac - GeForce RTX 2080 Ti 11 GB GAMING Triple Fan Video Card ($1379.99 @ B&H)
Case: Phanteks - Enthoo Pro ATX Full Tower Case ($99.99 @ Amazon)
Power Supply: SeaSonic - PRIME Ultra Titanium 750 W 80+ Titanium Certified Fully-Modular ATX Power Supply ($163.10 @ Amazon)
Total: $3146.48
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2018-11-14 03:28 EST-0500
Note: went over the budget a bit due to the current pricing.
Few words
What you'd loose in CPU performance, you'll make up with GPU performance. Also, while Core i9 has 8/16 cores/threads, making it's multi-core performance inferior to TR 2950X, it's single- and quad-core performance are better, making it overall better CPU than TR 2950X,
comparison:
https://cpu.userbenchmark.com/Compare/AMD-Ryzen-TR-2950X-vs-Intel-Core-i9-9900K/m569025vs4028
Since going with AIO would be a waste of money, picked Dark Rock Pro 3 as CPU cooler which is one of the best big-sized CPU coolers offering great cooling performance and good looks as well.
MoBo wise, picked MSI Tomahawk MoBo which is part of Arsenal Gaming series. MSI Arsenal Gaming series MoBos have a heavy emphasis on functionality and robustness, making this MoBo better suited inside the workstation/business PC rather than inside gaming PC.
Also, picked Corsair Vengeance LPX RAM (2x 16GB, 3000 Mhz) since it's one of the few RAM models that fits under Dark Rock Pro 3 without issues. Just install the RAM before installing CPU cooler, it's easier this way. With 4x RAM slots on MoBo, you can easily upgrade the RAM to 64GB in the future.
SSD is same as in herrwizo's build since 970 Evo is very fast M.2 NVMe drive and 500GB capacity also helps quite a lot.
With HDD, went with HGST (Hitachi) Deskstar NAS drive instead. Drive size is 4TB, just like your initial wish was. Oh, since HDD is NAS drive, it is designed to run 24/7 in a server environment, making it far more reliable HDD than consumer grade Seagate Barracuda drives,
review:
https://www.storagereview.com/hgst_4tb_deskstar_nas_hdd_review
Now the good part. There's RTX 2080 Ti in the build which is the fastest GPU in the world at current date and which would be the workhorse of this PC when it's used mainly as GPU render build. Also, compared to the RTX 2070, RTX 2080 Ti has more than twice of CUDA cores (4352 vs 2070) and GPU itself is about 50% better than RTX 2070,
comparison:
https://gpu.userbenchmark.com/Compare/Nvidia-RTX-2070-vs-Nvidia-RTX-2080-Ti/4029vs4027
For a case, picked Phanteks Enthoo Pro full-tower ATX case with side window. There's also windowless version at the same price if you don't like to see the internals of your PC case. Enthoo Pro is one of the best full-tower ATX cases out there and i did consider it heavily when i was searching for a PC case for my PC. For case being full-tower ATX, you have more than enough room for all the hardware with some extra space as well. Also included with the case is 200mm front intake fan and 140mm rear exhaust fan,
video review:
https://www.youtube.com/watch?v=cBhmn21ylkc
Since choosing a PC case is personal choice, feel free to switch out the case with the one that you like the most.
And lastly, put in the best 750W PSU money can buy at current date: Seasonic PRIME 750 80+ Titanium.
review:
http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=481
Note: This Intel build is only useful if you
mainly use GPU render. When you mainly use CPU render, go with herrwizo build instead since you'd get better performance with his suggested build.
Also, here's a good article for you to read about building a rendering PC, with which components to choose and why,
link: http://www.logicalincrements.com/articles/building-pc-3d-rendering-animation/