Why do I get sudden blank screens with sound?

For the last few days my Xbox has been booting up and running fine for about 5min to even a few hours into game play, but then suddenly chokes out into a blank random color tinted screen. The game will continue to run in the background and sound is still produced, but you can't see anything and the blank, sort of tint, changes colors based on the screen/menu you are on in game.

The HDMI cables were swapped as well as the tvs so I am assuming this is a GPU/or CPU issue? (last leg?...T_T)

Just want to know if buying another is the best solution or not...

*X360 Phat Pro*