Here's what I'd Do: This build is similar to the build I use personally however, it has been modified to fit your requirements... I've kept all the parts from one online store (amazon.com) to help simplify the ordering process. Also, Amazon tends to send orders in one package.
- i7 6700k has reasonable "overclockability" for additional performance when needed. e.g. when using CPU for rendering with cycles.
- The Thermaltake NiC C5 is rated for 230W TDP, personally, I have been able to render with the i7 6700k @ 4.8GHz under load.
- GTX 1080 (2 way SLI if you want to or separate): CUDA can also be used for rendering with cycles. They are overclockable with MSi Afterburner (again, for more performance while rendering). When using 2 GPUs, 2 tiles will be rendering simultaneously (1 tile per GPU). Having 2 GTX 1080s rather than one should come close to halving your rendering time. (the cards can't be in SLI when you want to utilize 2 rendering tiles)
- Motherboard supports CPU and GPU overclocking (includes SLI bridge)
- There's still a sizeable chunk of budget left for upgrades (more ram, additional disks etc...)
CPU: Intel Core i7-6700K 4.0GHz Quad-Core Processor ($337.00 @ Amazon)
CPU Cooler: Thermaltake NiC C5 99.1 CFM CPU Cooler ($58.34 @ Amazon)
Motherboard: MSI Z170A SLI PLUS ATX LGA1151 Motherboard ($132.90 @ Amazon)
Memory: Corsair Vengeance LPX 32GB (4 x 8GB) DDR4-2133 Memory ($181.77 @ Amazon)
Storage: Samsung 850 Pro Series 256GB 2.5" Solid State Drive ($128.14 @ Amazon)
Storage: Seagate Barracuda 2TB 3.5" 7200RPM Internal Hard Drive ($72.99 @ Amazon)
Video Card: EVGA GeForce GTX 1080 8GB Founders Edition Video Card (2-Way SLI)
($709.14 @ Amazon)
Video Card: EVGA GeForce GTX 1080 8GB Founders Edition Video Card (2-Way SLI) ($709.14 @ Amazon) (Access to the dual GPU bandwagon)
Optical Drive: Asus DRW-24F1ST DVD/CD Writer ($17.75 @ Amazon)
Operating System: Microsoft Windows 10 Home OEM 64-bit ($87.81 @ Amazon)
Case Fan: Corsair CO-9050016-BLED 52.2 CFM 120mm Fans ($24.49 @ Amazon) (It's a 2 pack)
PSU: Sentey XPP725-HS Xplus Power Supply 725w Pc Computer ATX Desktop Power Supply ($42.99 @ Amazon)
Case: Thermaltake Versa H22 Window CA-1B3-00M1WN-00 Mid-tower Computer Chassis (Black) ($43.55 @ Amazon)