PC shuts down while loading graphics intensive games

[zagoer]

I've been having this problem for a while and it's getting really frustrating. I've owned this build for almost 2 and half years. I've never really started having this problem until a few months ago. I can play League of legends and Counter Strike just fine. The only times it shuts down is when I'm Loading into Rust or Ark. Rarely if I manage to load in without it crashing. I've found a way to prevent it from happening as kinda. I downloaded Msi Afterburner and set all the Core and memory down to lowest. I also increased the fan speeds to max and I left power limit to default. I've also noticed if I load the game up with lowest graphics possible it helps. The weird part is that after I've loaded into the game I can max the graphics it runs perfectly fine. I have data wiped the hard drive and reinstall windows. I also tried to recently reapply thermal paste. I've tried swapping out my graphics card with my old GTX 750Ti. Please, I need help I'm running out of ideas. I've saved up all my money ever since I was 14 to build my dream PC.

My specs are

Graphics card: (originally had an EVGA GeForce GTX 750 Ti 2GB Superclocked.) I upgraded to an MSI GeForce GTX 970 4GB Twin Frozr V

Ram: (2 x 8gb) G.Skill Trident X Series 16GB

Processor: Intel Core i7-3770K 3.5GHz Quad-Core Processor
My CPU fan is the stock one you get from the box.

Power supply: EVGA SuperNOVA 750W 80+ Gold

Motherboard:MSI Z77A-GD65 Gaming ATX LGA115

Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM ( No SSD ) :c

Fans: I have 3 Cooler Master SickleFlow 69.7 CFM 120mm Fan ( 2 fans
mounted on the top blowing air out and 1 on the side pulling air in.)

 

[Jonathan Schiller]

Thermal problems usually come with bsod, where system shutdowns are usually a power issue. I would check your psu first. and remember to check it under full load, just because you have a stable 12v rail at a 200w load, doesn't mean it will be stable at 500w ECT.