I just got a new hard drive today (HGST 500gb, 2.5) to replace my failing hard drive (original 250gb Hitachi,2.5). I took my macbook in to Mac and they said the hard drive is failing so I just went ahead and ordered a new one. Now, when I get to disk utility via osx install disk, it fails to recognize the new hard drive. How can I get it to show up?