I've been having these random crashes for around a year now. What happens is that the screen would start flickering with what I would guess to be a result of graphics card failure, and then eventually completely freeze with a weird graphical glitch. I've already tried dusting out the computer, and I've already tried taking out and putting back the processor, graphics card, and RAM. My drivers are updated and I'm still having this problem.
Here is an example of the screen that appears when I crash: http://i.imgur.com/fyDewZj
Here is a video: https://www.youtube.com/watch?v=Ia50bUGQos0&feature=youtu.be
Processor: i5-3470 CPU @ 3.20 GHz, 3.60 GHz
Installed Memory (RAM): 8.00 GB
System: 64-bit Operating System, Windows
Display Adapter: AMD Radeon HD 7800 Series
Here is an example of the screen that appears when I crash: http://i.imgur.com/fyDewZj
Here is a video: https://www.youtube.com/watch?v=Ia50bUGQos0&feature=youtu.be
Processor: i5-3470 CPU @ 3.20 GHz, 3.60 GHz
Installed Memory (RAM): 8.00 GB
System: 64-bit Operating System, Windows
Display Adapter: AMD Radeon HD 7800 Series