Is this a good build? ($5k USD budget)

Solution
You can save $1000 of your money for only 5% performance decrease. This is much better: PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i7-5930K 3.5GHz 6-Core Processor ($554.99 @ SuperBiiz)
CPU Cooler: Cooler Master Nepton 280L 122.5 CFM Liquid CPU Cooler ($119.99 @ Amazon)
Thermal Compound: Arctic Silver 5 High-Density Polysynthetic Silver 3.5g Thermal Paste ($6.39 @ OutletPC)
Motherboard: Asus RAMPAGE V EXTREME/U3 EATX LGA2011-3 Motherboard ($479.99 @ Amazon)
Memory: G.Skill Ripjaws Series 32GB (4 x 8GB) DDR4-2400 Memory ($199.99 @ Newegg)
Storage: Samsung 850 Pro Series 256GB 2.5" Solid State Drive ($131.98 @ OutletPC)
Storage: Seagate 4TB 3.5" 5900RPM Internal Hard Drive ($144.99 @ Newegg)
Video Card: EVGA GeForce GTX 980 Ti 6GB FTW ACX 2.0+ Video Card (2-Way SLI) ($669.99 @ Amazon)
Video Card: EVGA GeForce GTX 980 Ti 6GB FTW ACX 2.0+ Video Card (2-Way SLI) ($669.99 @ Amazon)
Case: NZXT Phantom 820 (Black) ATX Full Tower Case ($206.99 @ SuperBiiz)
Power Supply: Corsair 1000W 80+ Platinum Certified Fully-Modular ATX Power Supply ($188.99 @ Amazon)
Optical Drive: Pioneer BDR-2209 Blu-Ray/DVD/CD Writer ($80.98 @ Newegg)
Operating System: Microsoft Windows 10 Pro OEM (64-bit) ($139.75 @ OutletPC)
Monitor: Asus PB287Q 60Hz 28.0" Monitor ($468.99 @ Amazon)
Total: $4056.00
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2015-10-04 01:26 EDT-0400
 
Solution


Is There really only a 5% difference between 2 Titan X's and 2 980tTi's?
 
Yep. The 980 ti only has 100 cuda cores less than the titan X. 6GB is plenty of vram also, if it's too little for some reason then go with fury Xes.

Also, 980 tis can be overclocked way higher than titan Xes, making a highly overclocked 980 ti faster than a titan X.
 


Cool, Thanks for the help!