How To Reduce Fan Noise in Mid-2011 iMac 21.5” (Model ID 12,1)

As an Apple Fan Boy, I had a good run with Apple devices. The horror stories I read in Apple Support Communities seemed to always happen to other people. Unfortunately, much to my disappointment, my luck ran out a few weeks ago.

My mid-2011 iMac started acting up and as it happens with these things, it did so a few months after Apple Care had expired. In other words, out of warranty and out of luck. The issue in question was that the following message kept popping up quite often:

Unapproved Caller SecurityAgent may only be invoked by Apple Software

The problem with the message appearing was that once it showed up, I couldn’t keep on using the computer until I did a hard re-boot, only to have it come up again an hour or so later (sometimes much sooner than that). Needless to say, off I went in search of answers at the Apple Support Communities. I tried every single suggestions offered on this thread. Oh the joys of trial and error when troubleshooting computer issues! By the end, all the symptoms pointed to the SSD drive’s cable. That’s right, a cable that wears out in less than four years, on a machine that’s essentially sitting still the whole time. If that’s not built-in obsolescence, I don’t know what is.

Now, I was faced with two options: take it to an Apple Store or an authorized reseller/ repair center. I went with the latter, since there’s one just 5 minutes away from my place. I told the person there what the issue was and what needed to be done. At that point I had tried everything, fresh OSX installs, NVRAM resets, etc. I was even considering buying OWC’s DYI kit to replace the hard drive. However, it was one thing to mess with the OSX, but to pry open my iMac and move things around seemed a bit more daunting. Anyway, the tech guy told me that they were going to run diagnostics on the machine anyway. A week later, they were finally able to find the problem, it was the SSD’s cable! If only they had listened to me, I would not have had to wait two weeks to get my machine back.

Now that the issue had been identified, I was once again faced with more decisions: get a replacement cable from Apple for $60 plus labor costs and tax or get a brand new 512GB SSD drive for $700+ plus installation and tax. You heard right, $700 for a 512GB SSD drive! Now, a BIG WORD OF CAUTION HERE, if you don’t need to upgrade your drive’s capacity, go with the cable option! The reason for the title of this article derives from my decision to upgrade the drive with a 3rd party option (offered by the tech). I wasn’t ready to pay Apple’s exorbitant prices for a drive that can be easily had for around $200-$300. The problem with going 3rd party is that Apple uses proprietary firmware on their drives (used to be supplied by Toshiba, not sure if they still are), which sends back readings to the system, such as temperature. As you can imagine, there’s no such firmware with the 3rd party drive, even though it also uses S.M.A.R.T. One of the issues that you might experience after the install is your computer fans turning on at full blast, thinking that your computer is overheating, when in reality all temperature readings are normal. In my case, my iMac worked fine for a week and then the fans started going full blast randomly and once they started, they never seemed to stop.

The fixes for the loud fan issue warrant a whole thread on the Apple Support Communities, which you can go to by clicking here. However, what ended up working for me was a little piece of free software called Macs Fan Control, which lets you see the speed your fans are spinning at and adjust them to ambient temperature. Problem solved! I hope someone out there, with the same iMac Model ID as mine (12,1), will find this useful. By the way, I had the iMac custom built by Apple (online store) with the 256 SSD drive option and a secondary 1TB HDD.

June 5, 2015
Juan Rojo

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