I have a Western Digital Green 2 TB drive attached to on of the two extra SATA II ports on my 2006 Mac Pro. No problems for over three years using several drives on this port. Today the drive suddenly would not mount and I received a "Drive Not Recognized" warning. In Disk Utility the drive is completely empty without any volume. I also now have a 32-GB "phantom" volume which used my user name - but does not exist. I turned off the computer and put the drive in an external enclosure, which it mounted without difficulty. I am now updating my backup of the drive and ordered a new 2 TB WD Black drive.
Only a few days ago I had the similar problem with a SD card - missing volume contents, a "phantom" 32 GB volume. I actually reformted and erased the SD drive, ran Disk Utility to check it, and put it in another computer - using the same SD card reader - and all the files were there!! Nothing was erased at all. Very strange.
Anyone have any idea WTF is going on? It seems like my motherboard drive controllers are getting flaky. Any way to test it? I have all the usual test programs, but nothing has shown up.
Thanks!

Only a few days ago I had the similar problem with a SD card - missing volume contents, a "phantom" 32 GB volume. I actually reformted and erased the SD drive, ran Disk Utility to check it, and put it in another computer - using the same SD card reader - and all the files were there!! Nothing was erased at all. Very strange.
Anyone have any idea WTF is going on? It seems like my motherboard drive controllers are getting flaky. Any way to test it? I have all the usual test programs, but nothing has shown up.
Thanks!