I just bought a Samsung ATA III SSD drive, the Samsung 850 EVO. I installed it in an external enclosure that I know works with an ATA II drive, but I don't see the new drive in Disk Utility. Thinking the drive was DOA, I exchanged it for a new one. This second one just arrived and I have the same problem. This is all on modern hardware (MacPro Tube, MacBook Pro Retina).
I can tell from reading the forums that others have gotten this drive to work, but what are the chances I would get two DOA drives?!? Pretty remote, I think.
Any ideas would be appreciated.