All games crash within 15 minutes of playing

[Rueduh]

So I just built my computer 1 week ago and since then I have not been able to play a game for more than about 20 minutes. I recently took it apart and put back in the stock cooler and was able to play for a good 4 hours without crashing. The next day it went back to normal and I am still continuously crashing no matter how small the game is (i.e Heavy bullets). I tried downloading minecraft to see if it was just steam games that were crashing but nope, minecraft crashed too, along with League of Legends. I have tried so many things such as checking temp while playing, checking my CPU and disc usage which reach very high even about 100% when playing. It seems to crash a lot faster when I play games online so I'm thinking that it may have to do something with insufficient permissions? I'm not too sure.

Specs:
ASUS H81M-A motherboard
Intel Core i5 4430
Crucial Ballistix Sport 16GB ram DDR3
NVIDIA GeForce GTX 950
Seagate 1TB Desktop HDD SATA 6Gb/s 64MB
EVGA 500 W1 80+, 500W Continuous Power

 

[Rueduh]

Have you tried re-seating the GPU?

No, this problem occurred even before I had my GPU, so that wouldn't really change anything.

Ah I must have missed that bit of info. Just to check as well, you mentioned that the GPU came after you put the PC together - did you change your connection from the onboard display output to a connection on the GPU?

I did not mean to pick that as the solution, lol.
But please elaborate I'm fairly new to pc and aren't to familiar with what that means.

 

[Hyboria]

Have you tried re-seating the GPU?

No, this problem occurred even before I had my GPU, so that wouldn't really change anything.

Ah I must have missed that bit of info. Just to check as well, you mentioned that the GPU came after you put the PC together - did you change your connection from the onboard display output to a connection on the GPU?

I did not mean to pick that as the solution, lol.
But please elaborate I'm fairly new to pc and aren't to familiar with what that means.

When you built your PC you said it was running but would crash when you were running games - and you were doing this before you installed the GPU? (if that isn't the case just ignore this). This means you would have had your monitor connected to the motherboard's display, lets say HDMI, output and it was running on the integrated graphics. If you then installed your GPU but didn't change the HDMI connection from the motherboard to the GPU then your PC is still running on the integrated graphics.

If this is the case then change your connection from the HDMI on the motherboard to the HDMI on the GPU. I hope that makes sense :|

 

[Rueduh]

Have you tried re-seating the GPU?

No, this problem occurred even before I had my GPU, so that wouldn't really change anything.

Ah I must have missed that bit of info. Just to check as well, you mentioned that the GPU came after you put the PC together - did you change your connection from the onboard display output to a connection on the GPU?

I did not mean to pick that as the solution, lol.
But please elaborate I'm fairly new to pc and aren't to familiar with what that means.

When you built your PC you said it was running but would crash when you were running games - and you were doing this before you installed the GPU? (if that isn't the case just ignore this). This means you would have had your monitor connected to the motherboard's display, lets say HDMI, output and it was running on the integrated graphics. If you then installed your GPU but didn't change the HDMI connection from the motherboard to the GPU then your PC is still running on the integrated graphics.

If this is the case then change your connection from the HDMI on the motherboard to the HDMI on the GPU. I hope that makes sense :|

Gotcha, the motherboard did have the VGA connection and when I installed the GPU I changed it over to the GPU, so should I only use HDMI or is the VGA fine?

 

[Hyboria]

Any connection on the GPU is fine, but preferably you'd want to use the HDMI as it outputs a digital signal. For a brief explanation watch below video:

https://www.youtube.com/watch?v=f38sotYHqtA

 

[Rueduh]

Any connection on the GPU is fine, but preferably you'd want to use the HDMI as it outputs a digital signal. For a brief explanation watch below video:

https://www.youtube.com/watch?v=f38sotYHqtA

So you don't think that would help my situation at all?

 

[Hyboria]

No I doubt it's going to fix the issue. If it was crashing both before and after you installed the GPU and you have your monitor connected to the GPU then it sounds like a hardware issue.

 

[Rueduh]

No I doubt it's going to fix the issue. If it was crashing both before and after you installed the GPU and you have your monitor connected to the GPU then it sounds like a hardware issue.

So are you suggesting I pick up a new hardrive?

 

[Hyboria]

Hardware not hard drive.

However, if you do have spares of each of your components, or an old rig laying around you should be able to find out which component is causing the issue by testing each component separately, one by one.