Building i7 4790k, first gaming computer, need input

That's a very nice high-end PC. I don't see any issues with it. The RM 850 has plenty of power even if you add another GTX 980 in SLI in the future. Enjoy the build!

nice build, only thing i'd change is the RAM, for gaming all you need is 1600mhz. Unless that's just as cheap as 1600mhz.

More expensive motherboard, than I think is really necessary, unless it has some features you really really want. I would go with an Evga G2 850w. It is an excellent PSU, and has a 10yr warranty, vs 5yr of the Corsair. Any particular reason you went with Win 8.1 pro? No real point, for a gaming rig. With the kind of money you are spending, I would go with something more like this.

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i7-4790K 4.0GHz Quad-Core Processor ($318.99 @ SuperBiiz)
CPU Cooler: Corsair H110 94.0 CFM Liquid CPU Cooler ($117.27 @ TigerDirect)
Motherboard: MSI Z97-GAMING 5 ATX LGA1150 Motherboard ($146.99 @ Amazon)
Memory: Mushkin Blackline 16GB (2 x 8GB) DDR3-1600 Memory ($124.99 @ Newegg)
Storage: Crucial M550 256GB 2.5" Solid State Drive ($90.98 @ Newegg)
Storage: Crucial M550 256GB 2.5" Solid State Drive ($90.98 @ Newegg)
Storage: Seagate Barracuda 3TB 3.5" 7200RPM Internal Hard Drive ($99.98 @ OutletPC)
Video Card: EVGA GeForce GTX 980 4GB Superclocked ACX 2.0 Video Card ($559.99 @ Amazon)
Case: Corsair Vengeance C70 (Black) ATX Mid Tower Case ($129.76 @ OutletPC)
Power Supply: EVGA 850W 80+ Gold Certified Fully-Modular ATX Power Supply ($128.99 @ SuperBiiz)
Optical Drive: Asus DRW-24B1ST/BLK/B/AS DVD/CD Writer ($16.98 @ OutletPC)
Operating System: Microsoft Windows 8.1 - 64-bit (OEM) (64-bit) ($92.00 @ B&H)
Total: $1917.90
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2015-01-09 10:46 EST-0500

Very nice as is.
I have some thoughts:

1. I7-4790K runs at 4.0.4.4 stock.
I would not use a liquid cooler.
My canned rant on liquid cooling:
------------------------start of rant-------------------
You buy a liquid cooler to be able to extract an extra multiplier or two out of your OC.
How much do you really need?
I do not much like all in one liquid coolers when a good air cooler like a Noctua NH-D15 or phanteks can do the job just as well.
A liquid cooler will be expensive, noisy, less reliable, and will not cool any better
in a well ventilated case.
Liquid cooling is really air cooling, it just puts the heat exchange in a different place.
The orientation of the radiator will cause a problem.
If you orient it to take in cool air from the outside, you will cool the cpu better, but the hot air then circulates inside the case heating up the graphics card and motherboard.
If you orient it to exhaust(which I think is better) , then your cpu cooling will be less effective because it uses pre heated case air.
And... I have read too many tales of woe when a liquid cooler leaks.
google "H100 leak"
-----------------------end of rant--------------------------

I suggest a noctua nh-D14/15 or phanteks with dual 140mm fans.
Your pc will be quieter, more reliable, and will be cooled equally well


I have become a bit jaded on the subject of haswell cooling for overclocking.
How high you can OC is firstly determined by your luck in the bin lottery.
I had high expectations from the Devil's canyon parts and their better thermals.
I found out that the thermals really do not matter unless, perhaps, you are a competitive overclocker.
Haswell runs quite cool, that is, until you raise the voltage past 1.25v or so.
Once you go past 1.3v, then you really do need very good cooling to keep stress loads under say 85c.
But, the consensus is that voltages higher than 1.30 are not a good thing for 24/7 usage.
I have been unable to find any official Intel recommendation on what is a safe vcore limit.
If you are an enthusiast, you can go higher.
Even if you can handle the heat, how much do you really need that extra multiplier from say 4.4 to 4.6?
My thought is that it is better to use the exotic cooling funds for a quieter and less expensive air cooler.
I suggest a good tower air cooler like noctua or phanteks with 140mm fans.

2. The ram is fine, but 1.5v 1866 speed will serve you equally well from a performance point of view.
There is perhaps a 1% difference in app speed or fps. To go faster requires more ram voltage that takes away from the cpu overclocking headroom.

3. Since you are planning on sli, you might want to consider a direct exhaust type cooler for your GTX980.
In a case, the top card tends to get starved for cooling air and a blower type cooler is more effective.
Here is one:
http://pcpartpicker.com/part/evga-video-card-04gp42982kr
4. On the hard drive, I think the barracuda drives are likely to be more problem prone than WD.
http://www.behardware.com/articles/881-6/components-returns-rates-7.html
Actually, I suggest you use a 500gb SSD and defer on the hard drive until you need the storage space for large files such as videos. It is easy to add a hard drive later.

5. Some first time tips:
a. Buy a #2 magnetic tip Philips head screwdriver for assembly.
b. Take the time now to read, cover to cover the manuals for the case and motherboard.

Addendum:
The Corsair RM-850 is the right size for sli, but it is only a tier 3 unit on this list:
https://community.newegg.com/eggxpert/computer_hardware/f/135081/t/45344.aspx?Redirected=true
I might suggest a tier 1 unit, the Seasonic X-850:
http://pcpartpicker.com/part/seasonic-power-supply-x850

1) Sabertooth:
I have the Z77 Sabertooth and the ASSIST fans are really annoying. I solved this by using the Asus Thermal Radar to turn them OFF if the temp is below 50degC (almost always). I have them setup to turn on for 1 minute after turning off the PC to remove heat from the shield.

The Maximus Hero VII has better AUDIO so that's worth considering, but the Sabertooth has a 5-Year Warranty. If you use headphones the Hero can output SURROUND virtually to stereo headphones from the front case connection.

2) CPU Cooler:
I recommend the Noctua NH-U12S instead. It's going to be SILENT in idle usage and very quiet under load. I've tested it.

The liquid cooler is overkill for this CPU at the stock 4.4GHz (no need to overclock further), will be noisier due to the PUMP and also has the possibility of failure which isn't much issue with an air cooler as it can still run quite well even without the fan.

3) Samsung 850 EVO:
No issue with it unless you can get the 840 EVO for cheaper. Just a reminder to install Samsung Magician.

4) GTX980:
In case you aren't aware this card is only about 15% faster than a similar GTX970. For the money you are spending you might want to consider two GTX970's instead.

While SLI isn't perfect you get higher frame rates when supported (up to 60% in some games comparing 2x970 to 1x980). In the worst case scenario if you get any major stutter disable SLI and run with one GTX970.

Using the second card for PHYSX instead can be ideal as well. If the game runs smoother on one card (main game on one card, PhysX on the other won't have any potential SLI stutter).

PHYSX on second card also ideal if game doesn't even support SLI at all (I'm talking 2xGTX970. May not be ideal with different strengths of cards).

5) START8 from Stardock for Windows 8

Windows 8 is ideal, however I can't give up my Start Menu. I have my system setup to boot directly to the traditional desktop and avoids the LOGIN window completely. I do have the new START SCREEN for Windows 8 used to organize programs I don't use as often which works really well (i.e. I have an "OFFICE" section for Microsoft Word etc).

6) STEAM ideal setup:
I have STEAM installed to my 3TB Seagate as games only benefit from faster loading times on an SSD but it's a lot more expensive for an SSD.

*I do have one SSD dedicated solely for games that benefit such as SKYRIM due to the fast loading times benefitting jumping around the map and entering buildings/dungeons etc.

Note you can MOVE games between two drives by backing it up, deleting it, then restoring the game from the backup but choose the folder on the other drive (can have more than one Steam folder). Thus I have:

250GB SSD #1 - for Windows and applications (it's slight overkill really but SSD prices have dropped)
3TB Seagate HDD - Steam, other games, downloads, media, Windows Backup Image using Acronis True Image..
250GB SSD #2 - games like SKYRIM where faster loading helps