My macbook has developed a problem where when the lid is shut and the power is connected it wakes up from sleep and then goes back to sleep and repeats this process every 30-60 seconds. What's weird is it doesn't wake from sleep and get stuck in this loop when the lid is open and the power is connected and I select sleep from the Apple menu when the lid is shut and the power is NOT connected and is running from the battery I recently updated my mac to Snow Leopard and put in a new HDD and since doing so the problem has been occurring. Any ideas what might be causing them problem?