Hi, over the last few days my Mac has started crashing more and more often. Sometimes the screen goes black but iTunes keeps playing, sometimes the screen freezes and I can still control iTunes with the keyboard, sometimes everything freezes, and iTunes goes into a loop repeating a fraction of a second of music over and over again (sounds like a car trying to start, and failing). I can't find my panic.log file anywhere. This could be related to my other thread about random horizontal lines here, but I don't know, there doesn't seem to be any connection between when the lines and the crashes happen. It's been suggested that this could be an issue with my ATI Radeon X1900 XT, but I really don't know where to start trouble shooting, if that is the case. I haven't installed any updates recently, apart from the Apple Java update which wouldn't appear to be related to this anyway. Any help would be greatly appreciated!!