Hi, I've had this happen to me intermittently for about a month now. My macbook would sleep randomly while surfing the web or just during any casual computing. It would clearly show an "X" on the battery bar after my macbook woke up. All this happens while on the battery. 2 days ago, I noticed that when on the adapter, I get an "X" on the battery bar, so my battery had died? My macbook is 5 months old with a 99% health rating on coconutbattery and istat. It clearly was not the battery. I took it to the mac genius, but she offered to just change the battery, saying that "this happened to my macbook, and trust me this will fix it." Well, it didn't. Now I get intermittent sleeps, but sometimes no "X" on the battery bar. This is really confusing. I need this macbook for college, and would like any help or advice on my situation. Thanks a lot! I spent a fortune on this 2.2 ghz blackbook, and I can't afford to buy new parts or a new computer. I pay my own University tuition!