New build crashing when playing games for 1 hour or more

This is a new build?

I can't be certain, but it is possible that with three sticks of RAM and only two channels, it might not care for it. See what happens with just two sticks of RAM in it and see if it behaves. Also, if you have attempted to overclock the RAM, it would mean that the overclock is unstable, and you need to lower the speed. (The RAM you have is rated at 1333 according to your list.) Check these things first, and let me know if it helped or didn't and then we can go on from there.
 

Maaz10

Commendable
Dec 30, 2016
2
0
1,510


i remove 1666 mhz ram and same problem