Two builds should I go with the slightly more expensive 5820k



I personally think saving $50 ~ $150 by not getting a SSD is not a bad choice. It's personal taste but SSD's do help a lot!

Anyways what is this build for?

If it is for gaming i think you will be better off with this:
PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-6600K 3.5GHz Quad-Core Processor ($239.99 @ Amazon)
CPU Cooler: Cooler Master Nepton 120XL 76.0 CFM Liquid CPU Cooler ($79.99 @ Micro Center)
Motherboard: Gigabyte GA-Z170X-Gaming 3 ATX LGA1151 Motherboard ($135.99 @ SuperBiiz)
Memory: G.Skill Ripjaws V Series 16GB (2 x 8GB) DDR4-3200 Memory ($144.99 @ Newegg)
Storage: Seagate Barracuda 2TB 3.5" 7200RPM Internal Hard Drive ($62.10 @ SuperBiiz)
Video Card: Gigabyte GeForce GTX 980 Ti 6GB Video Card ($678.99 @ SuperBiiz)
Case: Fractal Design Define R5 (Black) ATX Mid Tower Case ($97.99 @ SuperBiiz)
Power Supply: EVGA SuperNOVA GS 650W 80+ Gold Certified Fully-Modular ATX Power Supply ($79.99 @ NCIX US)
Total: $1520.03
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2015-09-01 11:53 EDT-0400
 
Build 1

1. Not a fan of the Z97-A..... neither are many others given the performance and high amount of dissatisfied owners on newegg. here's the performance ranking of Z97 Motherbiards based upon total fps of the games in Ocerclock3D's gaming test. Fastest card assigned value of 100%, others as a % of the fastest board. The leading boards have a 10% fps advantage over the Z97-A

MSI Z97 Gaming 9 - 100.00%
MSI Z97 Gaming 5 - 99.86%
MSI Z97A Gaming 6 - 98.96%
Asus Z97 TUF Sabranco - 96.13%
Gigabyte Z97X Gaming 5 - 95.00%
Gigabyte Z97X SOC Force - 94.95%
Asus Z97 Maximus VII Hero - 93.67%
Asus Z97 Maximus VII Formula - 93.58%
Asus Z97 Maximus VII Gene - 91.69%
Asus Z97-A - 89.57%
MSI Z97 Mpower MAX AC - 88.20%
MSI Z97S Krait SLI - 71.01%

Another ranking appears below .... based upon which boards might be best avoided. The % listed are the percent of board owners who posted highly negative (1 egg) user reviews. As you can see, the Z97-A is near the top of the "Most Unhappy Owners Club" w/ 27% giving the board just 1 egg

Gigabyte Z97X SOC Force - 29% http://www.newegg.com/Product/Product.aspx?Item=N82E16813128704
MSI Z97 Gaming 9 - 28% http://www.newegg.com/Product/Product.aspx?Item=N82E16813130808
Asus Z97-A - 27% http://www.newegg.com/Product/Product.aspx?Item=N82E16813132118
Asus Z97 Maximus VII Formula - 26% http://www.newegg.com/Product/Product.aspx?Item=N82E16813132247
Asus Z97 Maximus VII Hero - 19% http://www.newegg.com/Product/Product.aspx?Item=N82E16813132125
MSI Z97S SLI 19% http://www.newegg.com/Product/Product.aspx?Item=N82E16813130801
Gigabyte Z97X Gaming 5 - 14% http://www.newegg.com/Product/Product.aspx?Item=N82E16813128709
MSI Z97A Gaming 6 - 12% http://www.newegg.com/Product/Product.aspx?Item=N82E16813128709
Asus Z97 Maximus VII Gene - 11% http://www.newegg.com/Product/Product.aspx?Item=N82E16813132136
MSI Z97 Gaming 5 - 10% http://www.newegg.com/Product/Product.aspx?Item=N82E16813130770
MSI Z97 Mpower MAX AC - 4% http://www.newegg.com/Product/Product.aspx?Item=N82E16813130765
Asus Z97 TUF Sabranco - 3% http://www.newegg.com/Product/Product.aspx?Item=N82E16813132414


2. That memory has some rather poor timings @ 11-13-13-31 making it rather slow for 2133 by coimparison to the normal CAS 9 sets. $2 more gets you CAS 9 ( Timing 9-11-11-28 )
http://pcpartpicker.com/part/mushkin-memory-997121f
http://www.newegg.com/Product/Product.aspx?Item=N82E16820226687

3. With no SSD, I wouldn't be thinking about the WD Black at $112. For $25 less, you can have a drive that is more than 50% faster
WD Black = 6.34 MB/s
Seagate SSHD - 9,76 MB/s
http://www.tomshardware.com/charts/hdd-charts-2013/-17-PCMark-7-Gaming,2915.html
http://pcpartpicker.com/part/seagate-internal-hard-drive-st2000dx001

With the SSHD, you won't miss having an SSD.

4. With the release of the 980 Ti, the 980 has become somewhat irrelevant as it has left the 980 with a rather low, by comparison "bang for the buck".... this is a ranking of the current 9xx series cards based upon fps / dollar

970 - 3.97
970 SLI - 3.48
980 - 2.63
980 SLI - 2.30
980 Ti - 2.42
980 Ti SLI - 2.11

I'd try and move up to a 980 Ti or 970 SLI system to get better value / performance. And as far as which one, the SC series is the weakest among the "Big 4". The only difference between the SC and the reference series cards is the cooler. All the other guys have improved componentry, bigger VRMs, more power phases, augmented memory and VRM cooling making them a bit more robust. You can see these differences detailed in this 970 roundup article here on the bottom third of each page;

http://www.bit-tech.net/hardware/graphics/2014/09/19/nvidia-geforce-gtx-970-review/14

5. Recognizing that you love the case, it was also one of my favorites .... 5 years ago. Since then, newer cases have more to offer, better features, better cooling, more water cooling support, built in fan control / LED control, better cable routing. Not going to try to talk you out of it, just suggest take a good hard look before buying so as to not wind up w/ Buyer's remorse for not considering something that at the time ya didn't know about.

here's a nice comparison of 2 of the best here:

https://www.youtube.com/watch?v=GdWXLAmmSjc

Build 2

I can't make a case for an X99 based gaming build unless you have 3 or more GFX cards.... and the 750 watter is just a bit undersized or 2.

I'd stick with the faster (in gaming) 4790k build... tho besides the above suggestions, if this is a gaming rig, I'd consider dropping to the 4690k and spending the extra $100 on a 980 Ti or twin 970s. The twin 970s also gets you an extra $50 or so by selling the 2nd $60 game coupon.