I have a macbook air 2009 model. It worked fine till last week. When i was working with my air suddenly it become unresponsive. Track pad was not working. I did force shutdown by holding power button for few seconds. After that when I switched it on again, it just continuously beeps and the screen is blank. Last week also happened like this . But after sometime it switched on perfectly. And its not three beeps its continuous beeping. Pl. someone help!!