i bought my xbox 360 slim 250gb about 2 years ago. and all of a sudden yesterday it kept freezing. i couldnt even get to the dashboard it freezes when the xbox logo pops up. when the xbox logo begins to appear and does its spinning thing, the shadows under the logo keep flashing and are really glitchy then it jsut freezes, sometimes with the logo just frozen other times just as a white screen. ive tried everything any suggestions? and could this have been caused by overheating or something?