Mid 2011 iMac with Boot Issues

Karl,

Considering the computer is about 12-13 years old now you may want to consider replacing the computer. You can certainly install a SSD into it however the downside of doing so is you will still have a 2011 iMac that cannot run versions of Mac OS beyond 10.13.6 which is quite old now. In addition, the longer you keep it as a work horse the more you are painting yourself into a technological corner, meaning you will not be able to support third party apps, their updates, get repair parts for the computer etc...

Just some food for thought. Also, if you would like to post your EtreCheck report, sure we would be happy to look it over.

I understand the desire to keep the iMac in the game. That sounds like a failing hard drive. In case it is not failing, see if the computer is more stable if you boot into Safe Mode:

How to use safe mode on your Mac - Apple Support

Let the computer sit unused in Safe Mode for about 30 minutes, then restart as see if things are better. If not...well, the hard drive is now 11 years old which, in drive years, makes it absolutely "Old Testament" in age.

By all means please post an Etrecheck report but make sure you have the current version which is v6.something. You cannot simply copy and paste the report here--it is too long. To post, read this user tip on the subject:

How to use the Add Text Feature When Post… - Apple Community

If you're looking at 21.5" iMac models get one with 16 GB of RAM and as big a SSD boot drive as the budget can afford. That's because they can't be upgraded after purchase. Also, if not from Apple, make sure it's been prepared according to this Apple dccoumen: What to do before you sell, give away, or trade in your Mac - Apple Support. Otherwise you could be stuck with an expensive doorstop.

It appears that your boot drove is the bottleneck of performance:

 Write speed: 91 MB/s

  Read speed: 93 MB/s

You would be best served by getting an external SSD drive, cloning your boot drive to it with Carbon Copy Cloner and boot and run from the external. You could get read and write speeds in the area of

This is with this setup:

It's not as aesthetically pleasing as an SSD in it's own case but I find it was cheaper and I can swap out different bare SSDs depending on what I want to do.

I suggest you contact OWC (MacSales.com) Customer Support and see what they recommend for your particular Mac and budget from the variety of external SSDs that they offer. They are considered the premier 3rd party hardware provider for Apple computers.

And, you can easily take the drive with you when you move on up to a new Mac.

No one said you needed to buy another 27" iMac, new Mac Mini's are miles ahead in performance compared to a 2011 iMac and with a new display for less than $1500 you have a VERY nice solution. There are also Apple refurbished machines which have zero downside, they are identical to new, come with the same warranty as a new machine, are eligible for AppleCare and they save hundreds of $$$$.

In addition if you buy from Apple they have great financing, 12 months with zero interest. So really there is no reason to hold onto a 12-13 year machine. However the decision is totally up to you.

Yes, if you want to post your EtreCheck report we can take a look at it.

My guess is that the hard disk is starting to have read issues. It's a bit of a chore but I've installed SSD's on two 2012 iMacs. Depending on how many hours are on the drive but ten years is a long time for a drive to last.

First thing is do a Time Machine backup when you get it running as you're probably living on borrowed time. A 2tb external USB drive is under $100 on Amazon to back up the computer before it completely craps out. Just be sure it's formatted for exFAT. A Windows machine is easiest to reformat the USB drive IMHO. Just be sure it's exFAT.

A 2Tb SSD is about $200 and will really speed the machine up. It's not too hard to tear the iMac apart. Buy the adhesive cutting wheel and a new set of adhesive strips to glue it back together. It's kind of scary to take it apart but follow the videos.

Also buy one of the little sponge thingys to shim up the SSD to the same size as the original drive. https://www.owcdigital.com/ has videos on the entire process. It took me about an hour for my first iMac and then 30 minutes the second time. The rebuild process is a couple of hours but the Mac can do that on its own. If you have a network connection that's a lot faster than WiFi to download the operating system. Let me know if I can be of further assistance.

I meant the EtreCheck report does not show anything that would adversely affect the performance of the iMac.

My suggestion is to replace the computer with a more up-to-date Mac rather than spending anywhere from $50-200 on a computer that has zero value. I would invest in a new Mac mini (for a M1 based MM that has 16GB RAM and a 1TB SSD) it would be $1299, add another $150 for a new 27" display and you pay $1350. You can pay the Mac over 12 months or about $110 month and you have a brand new computer that far out performs your current device.

To me that makes a LOT more sense that trying to keep a 11-13 year old computer alive. But as I mentioned earlier, it is your decision.

Best of luck.

If the computer does what you want and money is tight replace the hard drive as that sounds like the problem. You're lucky the drive lasted this long. The new operating systems just add features and I think you can upgrade to Catalina which runs great on my 2012 MacBook Air. (Don't ask me how many computers I own! LOL)

Well, I see a some "possibles."

🔹 First, this:

Top Processes Snapshot by CPU:

Process (count) CPU (Source - Location)

photoanalysisd 17.46 % (Apple) ⚠️

mdworker (5) 8.44 % (Apple)

That process can go totally out of control and I am surprised to see it running at all. It really bogs down performance as higher levels. You can learn about the problem and how to deal with it here:

https://apple.stackexchange.com/questions/310594/what-is-photoanalysisd-and-why-is-it-using-77-of-my-cpu

🔹 Second, several of the crash notices flag "Memory." What brand and spec are your RAM upgrade modules?

🔹 Third. Respect EtreCheck's report of, "System modifications - There are a large number of system modifications running in the background."

See what you can live without, or at least disable temporarily for testing.

....................

We have the same iMac with the same hard drive specs. Your drive scores are, for all practical purposes, "on the nominals" for that class of drive. They are within 10 percent or less of scores our healthy 2011 iMac posts. The problem is that, even running at peak performance, that drive can never be fast.

👉🏻 The "external USB solid-state drive" workabout will not help on a 2011 iMac. To show any gain from that, the computer must have USB3 ports; yours was the last year Apple used USB2 ports in iMac. So that is off the table.

That leaves installing an internal SATA 6G SSD as the last option, either in the current hard drive's location or replacing the optical drive. That would produce a ~5X improvement in data transfer speeds. Neither are trivial tasks for the average end user, and the cost of professional labor to do it becomes questionable on an 11-year old computer. If you can afford US$150-175 in labor costs on top of the upgrade parts, that alters the "can I afford new?" discussion.

None of the normal subjects show up in your EtreCheck report.

Best of luck with whatever you decide you want to do.