My late 2012, 27 inch iMac ejects the external hard drives with some degree of regularity when waking the computer from sleep. The iMac is an i7, 3.4 GHZ computer with a 1 TB fusion drive and 32 GB of Ram. I am presently running mountain lion 10.8.4. I have listed what I have attempted to do to fix this issue but to date nothing has solved the problem to date. I also have a mid 2010 iMac with variations of SL, Lion and ML without any performance issues. If anyone has any ideas it would be appreciated.........
There is no lasting solution to the problem that I have found. I tried the following all to no avail:
1. repaired User (CMD+R) and main HD permissions files
2. reset NVRAM and SMC
3. Repaired HD with CMD+R but HD did not appear to be corrupted
4. Unchecked the "put the disk to sleep when possible".....though that made the least sense since that is only useful for the main hard drive
5. Deleted User/Library/Cache and HD/Library/Cache
6. Ejected all external disks manually and then shut off the power to each hard drive for a couple of minutes then reconnected them to the computer and the Belkin hub... .. connected all external HD to both computer and Belkin Hub
7. Replaced HD cables no improvement
8. Established an Admin User Account--still occurred
9. Safe Boot; note this happens on ML 10.8.4 on late 2012 iMac but not on my mid 2010 iMac.
10. Lastly, I performed a cleans install of 10.8.4 on the 30th of July, and one of my hard drive(s) ejected today the 3rd of August after waking the computer from sleep........
One of the Apple Care senior advisors had this to say.......... "I did receive some information on the issue we are having with the external hard drives. Starting with the 2012 iMac there has been a change to the sleep function. The 2012 iMac enters into a very low power hibernate mode. The reason the external drives are ejected intermittently is because the drives do not have firmware that can sense the low power state. Also the low power state is not automatically entered at each sleep cycle. The 2010 iMac does not achieve this lower power state and therefore the drives will have no problem staying connected to this iMac. We may want to contact the external hard drive manufacturer for firmware updates that can detect the lower power hibernate mode on the 2012 iMac. I did notice in our notes here that the issue did not occur in the test user. After reviewing with the engineering department this issue may still return because very low power hibernate mode with 2012 iMac. Please let me know if you have any questions so I can further assist you."
I contacted Western Digital and they indicated there is no available firmware update for WD essential desktop drives................ As you might imagine I am very disappointed with the questionable performance of the late 2012, 27 inch iMac. Any help would be appreciated.........
There is no lasting solution to the problem that I have found. I tried the following all to no avail:
1. repaired User (CMD+R) and main HD permissions files
2. reset NVRAM and SMC
3. Repaired HD with CMD+R but HD did not appear to be corrupted
4. Unchecked the "put the disk to sleep when possible".....though that made the least sense since that is only useful for the main hard drive
5. Deleted User/Library/Cache and HD/Library/Cache
6. Ejected all external disks manually and then shut off the power to each hard drive for a couple of minutes then reconnected them to the computer and the Belkin hub... .. connected all external HD to both computer and Belkin Hub
7. Replaced HD cables no improvement
8. Established an Admin User Account--still occurred
9. Safe Boot; note this happens on ML 10.8.4 on late 2012 iMac but not on my mid 2010 iMac.
10. Lastly, I performed a cleans install of 10.8.4 on the 30th of July, and one of my hard drive(s) ejected today the 3rd of August after waking the computer from sleep........
One of the Apple Care senior advisors had this to say.......... "I did receive some information on the issue we are having with the external hard drives. Starting with the 2012 iMac there has been a change to the sleep function. The 2012 iMac enters into a very low power hibernate mode. The reason the external drives are ejected intermittently is because the drives do not have firmware that can sense the low power state. Also the low power state is not automatically entered at each sleep cycle. The 2010 iMac does not achieve this lower power state and therefore the drives will have no problem staying connected to this iMac. We may want to contact the external hard drive manufacturer for firmware updates that can detect the lower power hibernate mode on the 2012 iMac. I did notice in our notes here that the issue did not occur in the test user. After reviewing with the engineering department this issue may still return because very low power hibernate mode with 2012 iMac. Please let me know if you have any questions so I can further assist you."
I contacted Western Digital and they indicated there is no available firmware update for WD essential desktop drives................ As you might imagine I am very disappointed with the questionable performance of the late 2012, 27 inch iMac. Any help would be appreciated.........