Saxman wrote:
Thanks for all that info. I will download and use the DriveDx to check my hard drive. So is Apple's Disk Utility not a reliable enough gauge when it says the drive checked out OK?
Disk Utility First Aid only checks the integrity of the file system. Disk Utility does not verify the health of the internal drive(s). Actually that is not quite true....Disk Utility will provide you with a "SMART status" of verified or failed, but from what I've seen this only alerts when the drive failure is extreme....most people would not be able to use the computer at that point. I've only ever seen Disk Utility report a "SMART Status failed" once, maybe twice in 20 years, but I've had to replace thousands of hard drives during that same period.
FYI, even the First Aid summary will lie to you....it is important to click "Show Details" and scroll back through the First Aid report to look for unfixed errors. Disk Utility is a terrible app overall as it is barely able to even do the simple task of erasing a disk/volume....many times failing at that for unknown reasons.
Many drives utilize an industry SMART health monitoring feature within the drives that will report on the health aspects of various drive systems. Unfortunately only a few of these SMART health attributes are actually useful for determining drive health...with SSDs, unfortunately there is even less use SMART health attributes these days. So monitoring & analyzing the SMART health attribute of a Hard Drive is very useful in determining the health of a Hard Drive (it can detect issues very early for over 90% of traditional drive failures in my experience). SSDs are another matter & are completely different as most SSD failures are quite sudden and involve the SSD's controller which is not being monitored.
Also, I do back-up with both TM & CCC.
Very good, I wish more people did this.
If the drive is failing, is it possible to install an SSD internally? My Intel iMac allowed me to add more RAM, so I wonder if replacing a drive is possible? I'll post results of the DD check, and maybe also an EtreCheck one, too.
Technically it is possible to replace the internal drive within an Intel iMac, but it is not easy to do. The Display Assembly has adhesive strips holding it to the frame and there are several difficult to see/access cables/connectors that are very delicate & easily damaged since they must be connected/disconnected while holding the display slightly separated from the frame. If one of these cables or connectors is damaged, it may render the iMac a brick since it may require a new Logic Board or Display Assembly (both extremely expensive). If the Display Assembly (glass & LCD panel) are not handled properly, it can easily crack under their own extreme weight. OWC sells drive upgrade kits including the adhesive strips & tools necessary for the repair and does provide installation videos (those video look much easier than it is in reality). I would not recommend this option unless done by an experienced professional.
It would be much easier to use an external USB3 SSD to boot the iMac as it would give you about the same speed as the internal SATA III controller. It is best to get a USB3 drive that supports the UASP for the best transfer rates (if using a hub/dock/adapter with the drive, then that should also support UASP). Of course Thunderbolt2 SSDs may provide faster transfers, but are usually much more expensive.
