Computer screen flickers and changes colors then crashes?

Hello, this is my first post here and I am not very good with this type of software so please, bare with me.

 

My specs are as follows:

- Intel i5 4690k

- Gigabyte R9 270 2gb

- Corsair 600w Modular PSU

- ASRock H97M Pro4 MB

- 8GB DDR3 RAM (forgot brand)

 

 

So here's my issue. I installed Assassins Creed Brotherhood on steam today and played for some time.  My game was going fine for like an hour then all of a sudden, the screen flickers up and down, changes some colors, and then crashes my computer. I had to restart it to get a response out of it. Later on, I tried to play some CS:GO, but the same issue happened. I actually recorded the issue in the video attached. (I apologize for the shaking I was showing a friend and was messing around)

 

After a while The screen gives me the error in the screenshot I attached.

 

So i updated my drivers to the latest version for my graphics card using AMD's software. Some games like rainbow six siege ran flawlessly fast, but the issue still persisted for my computer and kept crashing. Also, now games like minecraft (i know right), get like 30-60 fps from the usual 200. If it is also any help, my settings for CS:GO got reset, like sound, equipment, etc and im not sure why.

 

Can anyone help me out here? If you need more info let me know, I apologize for my ignorance in advance.