Please help, Possibly braking 360

For starters, I'm not allowed forsome reasononto The Broken XBOX 360 Discussion %26 Help Thread.Anyway, As I am playing my game will suddenly change the way it looks. It will get darker and look like... well, have any of you guys ever used the water color filter on photoshop? This happened completely at random and went on for the majority of my playing time.I checked the wires out, plugged and replugged and etc. Just for fun I put a fan on the next timeI turned on my 360and it didn't happen again but I'm not sure if it was a coincidence or if it is due to over heating.Basically is this what happens to your console before it shuts down??? It looks kinda' cool at first but it can't be a good thing. Should I take precautionary steps?