[BUILD] 2-3k Watercooled Build, What Do I Do From Here? Last Suggestions?

This is the build I was looking at, but changes most probably need to be made, if you could help that'd be great! Thanks!
PS, I don't have an SSD because I didn't know what size I should go with, 512gb? I wouldn't need more than 2 TB of HDD, I'm a pretty neat person when it comes to my files.

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i7-4790K 4.0GHz Quad-Core Processor ($324.99 @ NCIX US)
Motherboard: Gigabyte GA-Z97X-GAMING 7 ATX LGA1150 Motherboard ($169.99 @ Newegg)
Memory: Team Vulcan 16GB (2 x 8GB) DDR3-1600 Memory ($129.99 @ Newegg)
Storage: Samsung 840 EVO 120GB 2.5" Solid State Drive ($83.65 @ Amazon)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($51.99 @ NCIX US)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($51.99 @ NCIX US)
Video Card: EVGA GeForce GTX 980 4GB ACX 2.0 Video Card ($548.85 @ Amazon)
Case: Corsair 900D ATX Full Tower Case ($259.99 @ NCIX US)
Power Supply: XFX 650W 80+ Bronze Certified Semi-Modular ATX Power Supply ($64.99 @ NCIX US)
Keyboard: Corsair K95 RGB Wired Gaming Keyboard ($189.99 @ Amazon)
Mouse: Corsair Vengeance M95 Wired Laser Mouse (Purchased For $0.00)
Headphones: Audio-Technica ATH-M50 Headphones (Purchased For $0.00)
Total: $1876.42
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2014-11-20 10:00 EST-0500

3K budget...let's see...

5820K
X99 based motherboard
4x4GB DDR4 2400MHz
2x GTX 980's or 2x R9 290x's for 4K gaming
EVGA Supernova G2 850W PSU
900D

Are you planning on cooling both cards and the CPU with this? Have you checked out the water cooling sticky threads we have here?


EDIT: Thanks for the PM on your build...

I would still go 5820K and X99 platform as I believe the CAD stuff can benefit from it. As I mentioned above, you will need two high end vidoe cards to play the latest games on ultra at 4k resolutions.

I don't see any quad channel ddr4 ram in that list. Brand is mostly not relevent... as mentioned above, grab 4x4gb ddr4 2400mhz.

OKAY! I think I got it!

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i7-5820K 3.3GHz 6-Core Processor ($369.98 @ NCIX US)
Thermal Compound: Arctic Silver 5 High-Density Polysynthetic Silver 3.5g Thermal Paste ($3.98 @ OutletPC)
Motherboard: Gigabyte GA-X99-UD4 ATX LGA2011-3 Motherboard ($198.99 @ Newegg)
Memory: Corsair Vengeance LPX 16GB (4 x 4GB) DDR4-2666 Memory ($294.99 @ Amazon)
Storage: Samsung 840 Series 250GB 2.5" Solid State Drive ($149.97 @ OutletPC)
Storage: Western Digital VelociRaptor 150GB 3.5" 10000RPM Internal Hard Drive ($62.00 @ Amazon)
Video Card: Asus GeForce GTX 980 4GB STRIX Video Card (2-Way SLI) ($549.95 @ Directron)
Video Card: Asus GeForce GTX 980 4GB STRIX Video Card (2-Way SLI) ($549.95 @ Directron)
Case: Corsair 900D ATX Full Tower Case ($259.99 @ NCIX US)
Power Supply: EVGA 850W 80+ Gold Certified Fully-Modular ATX Power Supply ($109.99 @ Newegg)
Keyboard: Corsair K95 RGB Wired Gaming Keyboard ($189.99 @ Amazon)
Mouse: Corsair Vengeance M95 Wired Laser Mouse (Purchased For $0.00)
Headphones: Audio-Technica ATH-M50 Headphones (Purchased For $0.00)
Total: $2739.78
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2014-11-21 11:41 EST-0500

I am unsure about the HDD because it's a 3.5" and I don't know if I need a 2.5" or 3.5". There is a large price gap between the two. My only questions left are..

http://s856.photobucket.com/user/BTKLucky/media/IMG_1680_zps41a54f09.jpg.html
What fittings are used in this build? Any idea what fluid is used? Since there are two reservoirs I assume there are two radiators and pumps. I see the top rad, is there one in the bottom section of the case possibly? Thanks!