4K Build Please Help Check

I assume this will be a desktop...the ticket number you have up there is an old laptop with dual 680M GPUs.

You can add additional storage if you want (or you can use drives you already have and save the money). Also, wait a little while for UltraHD Blu-ray drives to come to market. This has closed loop water cooling for the CPU and both GPUs, so it'll be maintenance-free and have good performance when gaming for long periods.

Configuration URL:     https://www.digitalstorm.com/configurator.asp?id=1302287
Specifications:
Chassis Model: Special Deal Hot Seller - Digital Storm Coridium
Exterior Finish: - Standard Factory Finish
Trim Accents: - Standard Factory Finish
Processor: Intel Core i7 6700K 4.0GHz (Codename Skylake) (Unlocked CPU) (Quad Core)
Motherboard: ASUS MAXIMUS VIII HERO (Intel Z170 Chipset)
System Memory: 16GB DDR4 2666MHz Digital Storm Certified Performance Series
Power Supply: 1000W Corsair HX1000i (Digitally Controlled Power)
Expansion Bay: - No Thanks
Optical Drive: - No Thanks
Storage Set 1: 1x SSD PCI-E Card (400GB Intel 750 Series) (NVM Express) (Extreme Performance)
Storage Set 2: - No Thanks
Storage Set 3: - No Thanks
RAID Config: - No Thanks
RAID Card: - No Thanks
Internet Access: High Speed Network Port (Supports High-Speed Cable / DSL / Network Connections)
Graphics Card(s): 2x SLI Dual (NVIDIA GeForce GTX 980 Ti 6GB (EVGA HYBRID Edition)
Sound Card: Integrated Motherboard Audio
HPC Processor: - No Thanks
Extreme Cooling: H20: Stage 2: Corsair H110i GT - 280mm Radiator Liquid CPU Cooler (Extreme Performance)
H20 Tube Color:- Not Applicable, I do not have a custom HydroLux liquid cooling system selected
Chassis Fans: Standard Factory Chassis Fans
Internal Lighting: - No Thanks
Airflow Control: - No Thanks
Chassis Mods: - No Thanks
Noise Reduction: - No Thanks
LaserMark: - No Thanks
Boost Processor: Stage 2: Overclock CPU 4.5GHz to 4.8GHz (Requires High-End Motherboard Selection)
Boost Graphics Card(s): Yes, Overclock the video card(s) as much as possible with complete stability
Boost Memory: - No Thanks, Please do not overclock my memory
Boost OS: - No Thanks, Please do not tweak the services on the operating system
Windows OS: Microsoft Windows 10 Home (64-Bit Edition)
Recovery Tools: Windows Recovery Toolkit (Bundled with Windows CD)
Virus Protection: FREE: McAfee AntiVirus Plus (1 Year Service Activation Card) (Not Pre-installed) ($35 Value)
Office: - No Thanks
Game: - No Thanks
Display: - No Thanks
Surge Shield: - No Thanks
Speakers: - No Thanks
Keyboard: - No Thanks
Mouse: - No Thanks
Portable Gaming: - No Thanks
Branded Gear: - No Thanks
Priority Build: - No Thanks, Ship Within 10-15 Business Days After Order Is Successfully Processed
Warranty: Life-time Expert Care with 3 Year Limited Warranty (3 Year Labor & 1 Year Part Replacement)

in regards to the DS system ram:  i'm not sure if the memory modules they get from various vendors support xmp or overclocking with these baseline (i.e. Corsair "value select" series) sticks, you'd have to confirm with DS, but i suspect not.  i'm not really into overclocking memory, but i do like to set the xmp profile, so to be safe i'd choose the mid range memory line like the Corsair Vengenace LPX which supports XMP 2.0 if i were you.

here's an "Air version" Apollo: