Pc turning off during game

[Donarld]

While playing a game I get around 200-500 fps so my computer is extremely capable of running it. About 5 minutes into playing it thought my monitor will shut off. It still has the orange LED light running so it is on but it is if someone unplugged it from my PC so I have to do a hard shutdown of my PC. I have no clue why this is happening except for 1 reason. I installed the GTX 950 today and had lost the power cord that I run from the graphics card to my power supply. I bought more and used another 1 but I noticed 1 of the 2 molexs that I needed had 2 pins instead of 3 as you can see in this picture https://gyazo.com/7c8e58ffaf41896572625eb1d0cf5f96 It would be a great help if you have any and sorry if some of this is lacking since I am not the most knowledgeable PC owner.

 

[Emerald]

What is the make and model of your power supply?

I suspect your power supply not to be able to handle the gaming load of the video card.

the type of connector you are showing should not be necessary if your power supply is powerful enough.

As for the molex, the way it is correct because it uses three Grounds.

 

[Donarld]

What is the make and model of your power supply?

I suspect your power supply not to be able to handle the gaming load of the video card.

the type of connector you are showing should not be necessary if your power supply is powerful enough.

As for the molex, the way it is correct because it uses three Grounds.

I have A turblo link switch power supply model ATX-XG300W
50/60 hz frequency
115/230W voltage

The card said to have a power supply with 200w or more voltage and I have more.