Question Laptop shuts down when GPU is under load

[bojidar_darko2600]

At first i noticed that i cant run games as simple as cs:go. I just tought that the laptop was not strong enough to play such games so i used it primarly to play League of Legends. But now i cant even play League. The game starts but when a more intence team fight happends the laptop shuts downs. So I started to trouble shoot. At first i looked at the Event viewer and saw kernel power 41, but that just tells me that the laptop didnt shut down properly. I ran a UserBenchmark and noticed that when the program starts to test the GPU the laptop shuts down. Just to make sure i downloaded FurMark and as soon as i pressed that start button the laptop instantly shuts down. I thought maybe it was the GPU temps but the benchmark hasnt even started so it cant be, but i download MSI Afterburner just to be sure and the laptop is idling at around 75C and reaches 85-90 when gaming. Although a little high i dont feel like thats the issue. I could open it up and at least change the termal paste but its a lot of work and its not as simple as the other laptops. Maybe its the power supply. I dont know how to test it tho. I should also mention that i dont have battery on the laptop. I only use the charging cable.
Here are the laptop specs:

ASUS G750JM-T4040D​

Intel(R) Core(TM) i5-4200H CPU @ 2.80GHz 2.80 GHz
Ram: 12.0 GB 1333MHz
Intel HD Grapics 4600 driver version: 20.19.15.4624
NVIDIA GeForce GTX 860M (2GB GDDR5, GM107) driver version: 27.21.14.6627 / 466.27

In the Nvidia control panel i have set the GTX 860M as the main one. All power options on the laptop and the graphics card are set to performance.
Here is the Gpu clock speed from the Afterburner: 1019MHz
and the mem Clock: 2505MHZ

 

[bojidar_darko2600]

Update: I've decided to open open the laptop after i noticed that only the cpu fan was blowing. Turns out the gpu fan wasnt actualy blowing. It wasnt pluged all the way in. The gpu temps right now are between 40 - 46 idling. But still after i tried to bench the gpu laptop still shuts down instantly. At least now im 100% sure its not the temp. It must be something with the power... or the voltage

 

[bojidar_darko2600]

2nd Update: it was indeed the adapter. Although it was the one that came with the laptop it was not strong enough. It was 19v at 3.5amps. I swaped it with an 20v 4.5 amps and the laptop stopped shutting down. Ran Furmark and UserBenchmark without any issues. Even CS2 is running smoothly. Hopefully this helps someone else