docterkiwi

Try a different SATA port.

I was thinking similarly, Is there a short somewhere?  Probably not no standoffs because then the power lines from the psu would short and trip something/blow up something, but it could be a short somewhere.

I'd go up to 3200 memory if you're on Z370.

For GPU you'd probably be better off waiting for next gen then.
 
I would suggest a different PSU: CXM is similar in price and better; if you want something more expensive that's good Focus+ Gold, G2, RMx/RMi are all good choices.

I believe ARMA like fast single core performance, so an 8600K is a good choice there.
 

Why a locked board with an unlocked CPU?

I'd suggest going with 2 sticks of RAM to get some of that dual-channel, otherwise you're good. GPU may be a little outdated or bottlenecking, depending on what resolution you will be playing at.

Change the motherboard to an Asus Prime Z370-A.

Thank you guys so much.
 
 

i7-8700 performance is very close to the i7-8700K at stock. It is a 65W TDP cpu, so it runs much cooler and will be fine with its stock cooler.
A single stick of memory to leave the second slot open for an upgrade.
Case has a handle for convenient transportation.
 
PCPartPicker part list / Price breakdown by merchant
CPU: Intel - Core i7-8700 3.2GHz 6-Core Processor  ($359.00 @ B&H) 
Motherboard: ASRock - Z370M-ITX/ac Mini ITX LGA1151 Motherboard  ($131.89 @ OutletPC) 
Memory: Kingston - FURY 16GB (1 x 16GB) DDR4-2666 Memory  ($178.99 @ SuperBiiz) 
Storage: Samsung - 850 EVO-Series 250GB 2.5" Solid State Drive  (Purchased For $0.00) 
Storage: Seagate - BarraCuda 1TB 2.5" 5400RPM Internal Hard Drive  ($49.56 @ OutletPC) 
Video Card: EVGA - GeForce GTX 970 4GB SSC ACX 2.0+ Video Card  (Purchased For $0.00) 
Case: Silverstone - ML08B-H HTPC Case  ($70.04 @ Amazon) 
Power Supply: Corsair - SF 450W 80+ Gold Certified Fully-Modular SFX Power Supply  ($89.34 @ Newegg) 
Total: $878.82
Generated by PCPartPicker 2018-01-26 00:43 EST-0500

Here ya go, 1600 is the sweet spot for gaming.  Use this mod to get best thermals and throw 2 120mm fans in the gpu section.
 
 
PCPartPicker part list: https://pcpartpicker.com/list/M49nm8
 
CPU: AMD - Ryzen 5 1600 3.2GHz 6-Core Processor  ($187.39 @ SuperBiiz) 
CPU Cooler: CRYORIG - C7 40.5 CFM CPU Cooler  ($29.99 @ Amazon) 
Motherboard: ASRock - X370 Gaming-ITX/ac Mini ITX AM4 Motherboard  ($129.99 @ Newegg) 
Memory: G.Skill - Aegis 16GB (1 x 16GB) DDR4-2400 Memory  ($164.99 @ Newegg) 
Case: Fractal Design - Node 202 HTPC Case  ($69.99 @ Newegg) 
Power Supply: Corsair - SF 600W 80+ Gold Certified Fully-Modular SFX Power Supply  ($115.78 @ Amazon) 
Total: $698.13

Make sure you run sysprep before transferring your drive(s).

I haven't been up to date much with the newer hardware but this looks good to me. You'll be bottlenecked by your GTX 970 so upgrade that too if you need more performance. Also I'd wait for someone to give thier opinion on this build before you use it:
PCPartPicker part list: https://pcpartpicker.com/list/W3NsHN
Price breakdown by merchant: https://pcpartpicker.com/list/W3NsHN/by_merchant/
CPU: Intel - Core i7-8700K 3.7GHz 6-Core Processor  ($378.89 @ OutletPC) 
CPU Cooler: CRYORIG - H7 49.0 CFM CPU Cooler  ($34.89 @ OutletPC) 
Motherboard: MSI - Z370I GAMING PRO CARBON AC Mini ITX LGA1151 Motherboard  ($142.98 @ Newegg) 
Memory: G.Skill - Ripjaws V Series 16GB (2 x 8GB) DDR4-2400 Memory  ($169.99 @ Newegg) 
Storage: Western Digital - Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive  ($46.55 @ OutletPC) 
Video Card: NVIDIA - GeForce GTX 970 4GB Video Card  (Purchased For $0.00) 
Case: Fractal Design - Define Nano S Mini ITX Desktop Case  ($59.99 @ SuperBiiz) 
Power Supply: Corsair - CXM 550W 80+ Bronze Certified Semi-Modular ATX Power Supply  ($59.99 @ Amazon) 
Total: $893.28
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2018-01-26 00:10 EST-0500

i'd say these are all the height of your elbow->fingers if not less

you mean <$900 right? Also how small do you want it? like Mini ITX or a small mATX?
 
 

https://pcpartpicker.com/b/Lmmqqs
https://pcpartpicker.com/b/RXJ8TW
https://pcpartpicker.com/b/TD7WGX

Q1 

I might consider that thx
 

Well you already have a rig atm, why not wait for Ryzen, vega/volta? GPU prices goes down with new releases and ryzen may have cheaper options than intel; or even reduce the price of intel's offerings. 

Well run the game for a while, and record CPU, GPU, and RAM usage, as well as CPU and GPU temps. This is standard for every performance-related issue. Pls do this and give us the results.

I prefer MSI afterburner, it has all of these in one place, and can show you graphs of it over the entire gaming experience. It's alright, at least you are open to doing it. So much easier to help if you give us the data

jumping from an i5 4670k to an i5 4690k or i7 4790k isn't really that big of an upgrade imo.... just overclock your 4670k.

No problem playing Witcher 3 at 30FPS on a G-SYNC monitor.

But I can't jump on the hype train since I can't buy a ticket...

Something I've been working on recently