Game crashs

[ThePotatoMan1248]

Okay so my games crash at random and return me to my desktop. The computer is fine but my games crash Plants vs. Zombies Garden Warfare 2 and infinite Warfare are all I have. What is happening and how do I fix it. 

Asus p5k se/epu

Q6700 @3.2 ghz

6gb of ddr2

Msi rx 470

600w old power supply

2tb old segate barracuda

I'm thinking it's the hard drive or psu. What do you think I should.

 

Basically what are a few reasons why a game would crash.

 

Sometimes it gives me DirectX errors. Even though it's a fresh install of Windows 10 literally I did today

 

By the way as a side note I'm going to be upgrading AM4 platform as in as soon as AMD Zen comes out or intel kabylake or skylake so this is just a temporary.