Random and unexpected computer crash.

Hi there I have a problem that I hope you might be able to help me out with.
When I play FINAL FANTASY XIV: A Realm Reborn I have an issue that crashes my computer, displays a black screen and forces me to have to restart my computer.
This happens randomly and without any warning. I could be playing for 1-4 hours or even for just 10 minutes before it takes me to a black screen and locks up my computer.

So far this problem has only ever happened with this game and I have not been affected by any other game I own.
I have played around with different settings such as windows mode, borderless windows mode and full screen and also dropped my graphics down to the lowest to see if that would be effective, but to no avail.
Reading other posts I have also reinstalled the game and ran steam integrity checks.

Here I will post my computer specs via Speccy:
http://speccy.piriform.com/results/6...Zrb2jVRfF4iFdW

Any help you can offer would really be greatly appreciated in this matter.

What brand/model of power supply is in the system?