Hello! I'm looking for some help. hoping for a good Samaritan to help me out with some advice. Check this out: I have a Mac book Pro A1278 13'. The hard drive crashed, can't be accessible anymore so I bought another HD, kind of the same, but without the logo apple on it... has the S-ATA HD be compatible with mac? My MBP has this hd installed: Momentus 5400.6 500Gb PN: 9KAG34-041 with a Apple logo close to the bar code. And the one I got, hasn't the MAC logo on it... has to? -- When I put my OS setup disk, if the old HD is installed, I am able to see it on the Hard Drive Utility, but when I install the new one or any other SATA HD, like for example a 250Gb Sata HD, it just doesn't even recognize that there is a Hard Drive. I do not understand what could be wrong, been googling and seems like any SATA HD 2.5" should work on my mac, but, I can only see the old HD. By the way: after I saw it wasn't being recognized on my mac, I got the new hard drive and I partition it in another MAC book air using a USB SATA adapter and I was able to access it, mount it, copy a file and unmount from the OS. So the new HD is working great. The old one, can't be erase, partition or formatted. any help? Thanks in advance. PD. I am attaching a couple of pics with my two hard drives.