I've installed Windows 7 on my 2008 MacBook Air by bootcamp. Worked perfectly for couple of moths. Then this happened: *The "power on" led only lights up briefly when turning computer on then goes black *Win 7 takes ages to boot. >5 min. But works fine when boot finished. Then takes ages to shutdown. Once displayed bluescreen at shutdown which flashed by to quickly to read but said someting about power driver issue. *OSX boots fine, but power on led still wont work properly What could cause this? Battery needs to be replaced? Something more serious?