Imminent hard drive failure 2010 iMac 27, 2.93GHz

Hi I have a 2010 2.93GHz 27in iMac that is my main machine. It has both a 256GB Apple SSD and a 2TB Hitachi HDS722020ALA330 installed with the SSD running Apps and the system and the Hitachi used for my Home folder.

I use both iStat and SMART Utility to monitor the condition of both drives since a sudden failure by either would be catastrophic. I have an adequate back-up procedure in place but I don't want to be suddenly pressurised to replace either drive hurriedly in an emergency. Call it being prepared... 🙂

Anyhow, SMART Utility is warning me of imminent failure of the Hitachi drive containing all my data. However iStat passes both using SMART status. So which do I believe?

Looking online it seems that SMART Utility has a pretty good track record in detecting possible failures but I guess unlesss you actually wait for it to happen you can never be sure if the diagnosis is correct.

So I decided to prepare for the worst by ordering a Western Digital 4TB Caviar Black. I like WD and I like the five year warranty even more, however when it arrived I tried to format it. It was noisy spinning up and Disk Utility would not allow a format to take place even though it did actually see it in the list of drives.

I have since found out that internal drives on some iMacs must be replaced with those from identical brands - in my case Hitachi. Hitachi is now called HGST and guess who owns it - yup, Western Digital...

So, the supposed reason for needing an identical branded hard drive is to enable the temperature sensors to work avoiding the 'full-on fan experience'. In the past I have fitted other brand hard drives to other iMacs and used HDD Fan Controlto get around the issue but this is my own machine and I intend hanging on to it in as close to factory condition as I can. It's simply the best Mac I have owned in 20 years!

HDD Fan Control has worked very well but obviously I don't want to go down the road of stripping my main machine unneccessarily nor encountering compatibility or other problematic issues that further delay fixing the drive keeping my machine unavailable for work.

And there's the rub. It isn't yet a problem according to iStat. So which software should I believe and which 4TB hard drive should I buy to maintain an otherwise happy Apple experience with my beloved 2010 iMac?

Thanks for any helpful advice!

Rich 🙂