Hello everyone! Just recently I've built a brand new rig and it for the most part it works fine however, whenever I run a game and say have twitch.tv on as well on my other monitor after a certain period my unit will completely just freeze. Everything on screen will just freeze up and there's no sound and the PC will have to require a hard reset. I've tried all that I could to the best of my ability to asses the problem but unfortunately my knowledge on the issue is minimal. It can't be anything to do with dust because it's fairly new and I've also tried resettling the hardware as well. I can play certain games including League of Legends, Heroes of the Storm just fine but if I have something open in the background it will eventually freeze. Sometimes I can't watch twitch alone without it locking up. I've reformatted my PC and it still has the same issue. I've also run virus protection and it checks out clean. Any help will be much appreciated.
 
My specs are:
EVGA Z97 FTW Motherboard
Intel Core i7-4790K Devil's Canyon Quad-Core 4.0GH CPU
Corsair Dominator Platinum 16GB (2 x 8GB) 250-pin RAM
EVGA GeForce GTX 970 4GB 256-Bit GD GPU
Samsung 850 EVO 500GB SSD
Corsair RM850i 850W ATX12V PSU
Windows 10 64-bit
Thermaltake Theron Mouse
Razer BlackWidow Ultimate Keyboard
 
I snagged some information on the time of a freeze(couldn't screenshot because computer was frozen at the time):

I'm on windows 10. I also have windows 8.1 pro. It will freeze if say I'm watching a stream and playing a game at the same time. Some games run completely fine but others like Overwatch just recently crashed when put on high settings. I switched it to the lowest settings and it seemed to run fine(no freezing). Watching a twitch stream for a while will also cause it to freeze as well (on the browser).
 
What would be some steps to help diagnose the issue?

Okay awesome I'll try all of these methods out. Also it doesn't freeze while idle only mostly when running programs and games.

Okay here are the results from memtest:

5 passes and everything seemed to check out okay.
Tested each ram stick one at a time and still the same issue both times.
What should I be looking out for in PSU testing?

OK that mean your memory is not problematic. 
Did you tried AIDA64 CPU/FPU/CACHE/MEMORY STRESS 2-3h?
If freezing happen when power consumption become bigger, during gaming or higher load of graphic card than one of that two hardware could make problem as well. Lets continue with testing CPU and later heavy 3D stability testing in DX11 applications.
What happen last days? Did you had freezing again and when?
 

Hey Crilix so I disabled Turbo mode and it did make a difference I did notice so I'm guessing(hopefully) temp has something to do with it.
Currently don't have a cooler cause I didn't think I'd need one but that seems it might be the case. Idle I'm around 35ish and load i'm around 50-60ish compared to high 60's 70 ish.
Also ispasion22 I couldn't understand the pm bc it was in a different language.
I did notice some performance loss(understandable) from turbo mode and I would like to keep it on but without proper cooling that's not possible it seems.
 
Going to try installing cooler and see if it fixes the issue.

Cocolosh
Hey Crilix so I disabled Turbo mode and it did make a difference I did notice so I'm guessing(hopefully) temp has something to do with it.
Currently don't have a cooler cause I didn't think I'd need one but that seems it might be the case. Idle I'm around 35ish and load i'm around 50-60ish compared to high 60's 70 ish.
Also ispasion22 I couldn't understand the pm bc it was in a different language.
I did notice some performance loss(understandable) from turbo mode and I would like to keep it on but without proper cooling that's not possible it seems.
 
Going to try installing cooler and see if it fixes the issue.

Welcome to the form Cocolosh,
 
Do you have a heat sink & fan on the CPU? Stock Intel cooler will barely work - not good for OC (overclocking)
 
Did you verify the RAM voltage in BIOS is set to the mfg. specifications?
 
edit:typo

So disabling the trubo on the cpu fixed the freeze? If so, are you running the latest motherboard bios?

Have you tried any older bios versions to see if it helps restore turbo mode without the freeze? If not, try it. 70C is nothing for the 4790k.

Cocolosh
Yes trying older versions was one of the first things i tried.

Hmm. That sux. It's either the cpu/mb/bios then.

Sure thing:

 
Case is Thermaltake Chaser Series Chaser MK-I

I suggest you use HWMonitor to know the maximum value of CPU, chipsets, GPU or (why not?) HDD. 
Use Prime95 to stress the CPu: 20min small fft and supervise the temperature rises until it stabilizes. Make screenshot with maximum temperature reached after 20 minutes of running Prime95. If you take bluescreen, you should know the latest maximum temperatures.
Take a look with AIDA or Crystal DiskMark for HDDs SMART attributes and take screenshot.
Post screenshots here.
Good luck.

Wow and I thought it was just me. I had similar issues on my Z97 FTW after I upped to bios v.2.0. Memtest said I had bad ram, lots of freeze/crashes in Photoshop, all-in-all just wonky performance even after defaulting most settings in bios. I tried all of the suggestions from above posters with no luck. That said, I backed down to bios v. 1.08 and no more problems!