I did this just for an estimate, agreeing with the above, but this is $50 over the $2000 budget, but is extremely future proof.
PCPartPicker part list:
http://pcpartpicker.com/list/BWqckT
Price breakdown by merchant: http://pcpartpicker.com/list/BWqckT/by_merchant/
CPU: Intel Core i7-6700K 4.0GHz Quad-Core Processor ($329.99 @ Newegg)
CPU Cooler: Corsair H100i v2 70.7 CFM Liquid CPU Cooler ($104.99 @ Newegg)
Motherboard: Asus MAXIMUS VIII HERO ATX LGA1151 Motherboard ($199.99 @ B&H)
Memory: G.Skill Ripjaws 4 Series 16GB (2 x 8GB) DDR4-2666 Memory ($88.99 @ Newegg)
Storage: Samsung 950 PRO 256GB M.2-2280 Solid State Drive ($184.99 @ B&H)
Storage: Western Digital Caviar Black 2TB 3.5" 7200RPM Internal Hard Drive ($129.88 @ OutletPC)
Video Card: EVGA GeForce GTX 1080 8GB Superclocked Gaming ACX 3.0 Video Card ($644.99 @ B&H)
Case: Cooler Master MasterCase Maker 5 ATX Mid Tower Case ($169.99 @ B&H)
Power Supply: EVGA 850W 80+ Gold Certified Fully-Modular ATX Power Supply ($118.99 @ NCIX US)
Operating System: Microsoft Windows 10 Pro OEM 64-bit ($98.99 @ My Choice Software)
Total: $2056.80
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2016-10-20 10:18 EDT-0400
You may have forgotten the OS, you can change this for Windows 7 if that is your preference, so I removed the SSD and added a 2TB WD Black HDD, you can change this to 1TB for around $40 back.
I also removed a 2x8GB kit of RAM, as 32GB is not needed for gaming on its own, and just left the one kit in there.
If you want it closer to the $2000 mark, go for a cheaper case, as said above.