New Gaming Build

[Crash55]

It has been 4 years since I built my last PC and the only internal component I have upgraded was the video card (GTX 690 to GTX 980Ti). Below is a notional build. I am looking for any and all input on what it is good or bad.

Time frame - By the end of Jul (spare Windows 8 code I can use to get Windows 10 free)

Budget - Whatever it takes within some reason.

Usage - Primarily gaming. Occasional CAD, photo and video editing.

Existing Components - Monitor (Dell P2715Q - 4k), Keyboard (Logitech G11), Mouse (Logitech G502), Speakers (Klipsch Pro Media Ultra 5.1), Power Supply (EVGA 1200 P2 - got it half price when I bought the 980 Ti)

Possible Components:
Case: Cooler Master HAF X (I used for my last build and like the front hot swap bays)
Video Cards: Two EVGA 1080 GTX FTW
Motherboard: EVGA X99 FTW K
CPU: Intel Core i7-6950X
CPU Cooler: Thermaltaek Silver Arrow or Noctua NH-D15
Memory: Gskill TridentZ Series 4 x16GB
Boot Drive: Intel 750 Series 1.2TB
Data Drive: WD 4 TB Black
Optical Drive: LG WH14NS40
Firewire: Vantec 3 port (need it for scanner and video camera)

I am not wed to any particular store or component at this point. I have no desire for water cooling. Tell me where I can improve.

 

[Crash55]

Reading online I see that the Noctua NH-D15 will block the first PCI slot. Looking at Thermaltake's website it appears that the Silver Arrow IB-E is designed to clear the first slot.

 

[Bearmann]

For gaming, CAD, and Photoshop a CPU with a faster single core ability would be better. I would go with an 6850 instead. Noctua lists a compatability chart with all of their coolers. Sometimes the first slot is a x1 or x4, so it doesn't matter if it is blocked.

 

[Crash55]

On all the boards I have looked at the first slot is x16. So I need it.

It looks like both the Thermalright Silver Arrow IB-E Extreme and Le GRAND MACHO RT have offset fins to avoid the first slot. They also look like they cool on par with the Noctua NH-D15S.

The 6850 is cheaper so that is good. I wasn't sure if I needed the cores or the speed more.

Thanks