What RAM would be best 2x8g or 4x4g ?

[elwolfe121]

Hi I'm new to PC building, and I'm going to be building this soon. I'm wondering if 2x8g or 4x4g RAM is better for my system.
Also how can I find this out on my own what spec do I need to look for and on which component?

PCPartPicker part list: http://pcpartpicker.com/p/qkPQt6
Price breakdown by merchant: http://pcpartpicker.com/p/qkPQt6/by_merchant/

CPU: Intel Core i7-5820K 3.3GHz 6-Core Processor ($374.99 @ SuperBiiz)
CPU Cooler: CRYORIG H5 Universal 65.0 CFM CPU Cooler ($46.99 @ Newegg)
Motherboard: MSI X99A SLI PLUS ATX LGA2011-3 Motherboard ($209.41 @ B&H)
Memory: Corsair Vengeance LPX 16GB (4 x 4GB) DDR4-2133 Memory ($99.99 @ Amazon)
Storage: Samsung 850 EVO-Series 250GB 2.5" Solid State Drive ($82.99 @ Newegg)
Storage: Western Digital BLACK SERIES 1TB 3.5" 7200RPM Internal Hard Drive ($73.89 @ OutletPC)
Video Card: MSI GeForce GTX 980 Ti 6GB Video Card ($623.00 @ Amazon)
Case: NZXT Phantom 530 (Black) ATX Full Tower Case ($119.99 @ SuperBiiz)
Power Supply: EVGA 850W 80+ Gold Certified Semi-Modular ATX Power Supply ($74.99 @ Newegg)
Optical Drive: Asus DRW-24B1ST/BLK/B/AS DVD/CD Writer ($17.78 @ OutletPC)
Operating System: Microsoft Windows 8.1 Pro OEM (64-bit) ($126.07 @ Amazon)
Wireless Network Adapter: TP-Link TL-WN822N 802.11b/g/n USB 2.0 Wi-Fi Adapter ($19.89 @ SuperBiiz)
Total: $1869.98
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2016-01-30 04:47 EST-0500

Thanks for any help!

 

[Ironsounds]

Hello... if Quad channel 4x4 and you have it. B )

 

[bignastyid]

X99 is quad channel so the 4x4gb set would be better.

 

[azaran]

With the X99 boards running quad channel, 4x4 would give you better performance than 2x8, however it'll reduce the total memory you can throw in to it over time if you upgrade to higher amounts.