Hey! If you ever want to create a false-positive for bad RAM in the new MacBook series, I’ve got a foolproof way to do so!
You’ll need two MacBooks. Put them both on a flat surface. Close one of them, then set the other MacBook on top of it. Power up the top MacBook. It will start up, and a few seconds later the power light will start gently pulsing but the screen will remain black. No matter what keys you hit, it won’t wake up.
Ta Dah! Those are the symptoms of a failed Power On Self Test due to bad or missing RAM.
What’s actually happened is that there’s a little rare-earth magnet in lid of MacBook that closes a switch in the body of the MacBook when the lid is closed. The magnet in the bottom MacBook is closing the switch in the top MacBook. The top MacBook will not wake up – as far as it is concerned, its lid is closed.