Ok, so I got my iBook almost 3 years ago exactly... Xmas 2005, the last model they produced. And for those almost 3 years, it worked perfectly. Now, last week my iBook froze for the first time ever, and it just happened again today, forcing me to hold down the power button and restart. Why would my iBook all of a sudden start freezing on occasion, and is this a sign of something worse?