Here are the previous threads about this issues was having. http://forums.macrumors.com/showthread.php?t=721345&highlight=imola+ghost And another.... http://forums.macrumors.com/showthread.php?t=706182&highlight=imola+ghost I finally after all of this I decided to put back in my factory hard drive and my laptop has been very good and reliable since then. It's only been several days with light use but overall I can tell that it just runs smoother and without any beach balls. Now I want to know, why would this hard drive make my laptop act the way it was? The hard drive seems compatible does work but does so with lots of spinning beach balls and hang ups with very frequent restarts by holding the power button down. The odd thing is, is that I originally bought the hard drive and then had problems, took it back and bought another one and it seems to be the same with that same but new hard drive in. Why? I'm really need and want this bigger hard drive to be located locally and not external but I'm afraid to spend more money on another hard drive. Is there a hard drive that is known to work with this Macbook of the 500gb size? I find it hard to believe I got 2 bad hard drives from the same manufacturer but what do I know.