Playing along...
CPU:- i7 5960X - 4.4Ghz
MotherBoard:- Asus x99 Rampage V Extreme
Cooler:- H110
PSU:- Corsair AX1200i
GPU:- AMD Sapphire Vapor-X 290X 8GB x2
Ram:- 32gb 4x8 3000Mhz DDR4 Corsair Dominator Platinum
SSD:- Samsung 1TB 850 PRO SS
HDD:- 6TB x4 Western DigitalMonitors: 3X 32inch monitors each have 2560X1440 resolution
Now this it probably what you'd "need":
i7 5820k [Save money here,]
A much cheaper mobo ~$225 [...and here,]
Cooler Master Hyper 212 [I've seen people use this on a 5820k OC'd to ~4.4GHz]
GPU: Dual GTX 980Ti 6GB SLI or FuryX 4GB Crossfire [ ...then spend that money here.]
RAM:16GB 4x4GB [Even with mods, you should be hard pressed to max out 16GB. Also, i7 Extremes use quad-channel memory, which is double the bandwidth at the same clocks over dual-channel most gaming machines use. Memory speed doesn't really matter here, better off just looking for a reliable memory set ...meaning a set that has a lot of reviews on newegg and few 1-2 egg reviews ...less than 10%.]
PSU: http://www.newegg.com/Product/Product.aspx?Item=9SIA24G28N0888 [http://www.jonnyguru.com/modules.php?name=NDReviews&file=print&reid=389]
SSD:- 2-1TB SSD [Samsung has been having some bugs lately] [1-SSD for OS-Uplay-Origin-GOG/1-Steam]
HDD:- 2-2TB Western Digital [...for general media if you need, but you really should have a separate HTPC.]
And don't forget: Monitors: 3-4k 40" Curved Monitors
...Curved! Monitors!