PC crashes after playing for about 10-15 minutes

Hello,
I have a problem with my game. After playing the game about 10-15 minutes my computer crashes or in detail:
It's just like the electricity would be switched off and then my computer starts up like normal again, without that I am doing anything. It doesn't happen while playing other games.
Please help me!

My Computer:
OS: Winows 10 Pro 64-Bit-Version
CPU: Intel Core i7-2600 @ 3.40GHz
RAM: 8 GB
GPU: AMD Radeon HD 7800 Series
SSD: Samsung 850 Evo (500GB)

 

Thermal Shutdown. It's not the game's fault. Check your cooling system
--- Post updated ---
Edit: @Nadeox1 beat me to it...

 

Ok, i'll do that. Thank you!
I will send the results later.
--- Post updated ---
Okay, here are the screenshots. The last screenshot was made after the startup after the crash. But the temperature was at one point even at 79°C.
I played with one AI on the Map Utha.

 

So here is the screenshot from the GPU temp. I only got one screenshot... But I know that the temp got up to 80°C.
Now I will do the other test.

 

Clearly doesn't look like stock core clock speeds (up to 4.3GHz) and Vcore 1.288. Also bus speed at 103 which also push your RAM and it may not work stable. Put bus speed to default (100) and check if it will be stable.

Edit:
From stock 3.4GHz to 4.3GHz on i7, well that's a lot and it may need higher Vcore, but it will result in higher temps so I don't recommend it. Seems like you set clock speed to 4200MHz and bus speed to 103 which gives 4326MHz so looks like I'm right about it. (look at latest screenshot you uploaded and max speed of cores #3 and #4)

 

Okay. But it also crashed bevor I did this in my BIOS from my Asus P8P67 Mainboard. So I don't really know of this is the problem... But I will reset all to normal.
--- Post updated ---

So now I am doing the test for about 15 minutes and it hasn't crashed yet...

 

Okay now I switched the Overclocking off and without harder crashes ingame it works good. But when I switch on Full screen mode or have a harder crash, the computer crashes.

 

Like I said bevore: It turns off like when you turn the electricity off but automatically starts up again.

 

Could be his power supply, given his computer just shut's off like someone pulled the plug. Under the assumption that his power supply is also from the sandy bridge era.

 

So... I can say that nothing should be damaged because I am doing this stresstest for about 10 minutes and now while I'm writing and nothing happend. I also made some screenshots for you.
--- Post updated ---

Yes it could be the power supply because it's about 5 years old, but then tell me why this doesen't happen while the stress test or while playing other games with such a brilliant graphik?

 

Because games usually aren't that demanding on GPU, RAM and CPU at once for that long period of time, stress test is stressing only one thing, so that mean when you play BeamNG it consumes more power than for example playing GTA V or stress test would. And some calculations are more demanding than others so you can have 100% load and your CPU will stay at 50*C and you can choose 1st option in Prime95 (this about small PFT and high Temp) and I can guarantee you it will stay over 80*C or throttle, similar with GPU. + all of your hardware isn't that new. It looks like your PSU can't handle it anymore, you may look at the state of inside of your PC cleaning it isn't a bad idea, changing thermal grease on CPU could help a bit too if it have more than 2years. Anyway this OC shouldn't damage anything inside your PC too low temp and Vcore. If you can borrow from someone another PSU (~500Watt or more ) and try if it will work then. As I see you have Win10 so every "overOC" will do a BSoD but not cut off power completely. -So it's clearly hardware issue.

 

Its your power supply. Mine was slowly going bad and would shut down just as you explain in your post. It eventually got so bad that it would shut down in really simple games like Garry's mod. It never shut off during stress test or heavy workload applications. I got a new power supply and the issue went away! 5 years old is pretty old for a power supply, especially one for which you don't know the name of. I would recommend an EVGA GS/G2/P2 power supply as those are built well and fairly priced. Don't buy a really cheap power supply because most of them don't output their rated wattage and will deliver power in less optimal ways that could damage sensitive components.