iMac late 2012, Intel Core i7 and 16GB memory running slow

I agree with den.thed. With an i7 processor and 16GB RAM, your iMac should not as severely affected by Chrome as lesser-equipped 21.5i Macs. However, this section shows Chrome and its minions are still using far to much of your CPU capacity:

Top Processes Snapshot by CPU:

Process (count) CPU (Source - Location)

Google Chrome Helper (Renderer) (28) 45.64 % (Google, Inc.)

Google Chrome 21.00 % (Google, Inc.)

Google Chrome Helper (GPU) 20.42 % (Google, Inc.)

WindowServer 13.52 % (Apple)

kernel_task 6.70 % (Apple)

Add it up. In some cases that can be due to leaving certain websites open in the background but, as Chrome is a known resource hog on both Mac and Windows computers, it's probably Chrome on an eating binge.

I see a couple of other things that could be contributing:

User Login Items:

  Backup and Sync.app (Google, Inc. - installed 2019-09-28)

    (Application - /Applications/Backup and Sync.app)

and Microsoft OneDrive.

Web-based backup schemes can slow you workflow as they "phone home." If you must use them, keep what is on the server to a minimum, and remove files once the are no longer needed on the server.

Your hard drive is not fast to start with but is running more slowly than I expected. It could partly be the load Chrome inflicts so I'd rerun the test after shutting down Chrome to see if read/write scores improve. This was your drive performance:

Performance:

System Load: 1.39 (1 min ago) 3.54 (5 min ago) 3.56 (15 min ago)

Nominal I/O speed: 0.16 MB/s

File system: 20.47 seconds

Write speed: 69 MB/s

Read speed: 46 MB/s

For comparison, we have a geriatric Mid 2011 21.5 iMac still in service that has the same slow 5400rpm, 3GBps hard drive as yours. Note the speed difference:

Performance:

    System Load: 1.62 (1 min ago) 1.67 (5 min ago) 1.87 (15 min ago)

    Nominal I/O speed: 0.05 MB/s

    File system: 38.28 seconds

    Write speed:  112 MB/s

    Read speed:  91 MB/s

That is a big difference. den.theds' suggestion for an SSD in an external enclosure should work, and several of our long-serving helpers here have done exactly that and are happy with the improvment. Because Apple chooses to install slow SATA 3GBps mechanical hard drives, your max data transfer rate now is 3GBps. USB3 can transfer at up to 5GBps.

For this to work, the external drive must be rated at USB3 and the SSD must be a 6GBps model. The cheap ones you get from the office supply store may not meet these specs. I've found their makers rather stingy with the tech data they put on the boxes of these entry-level devices. Best to get a pro drive and enclosure separately so you know what specs you bought.

Base on what I am seeing on my MacBook Pro with a aftermarket SSD on an internal 6GBps bus, I'd estimate your read/write scores could be in the 350-400MB/s range with the proper SSD external boot drive.

MCovrig1 wrote:

I did a check on a MacBook Pro i5 8Gb late 2014 i'm using and it gave me a much better result: Write 646 and read 777; so there's deffo something wrong with my iMac.

I'll try the external SSD suggestion in the next few days and see how it goes. I'll keep you guys updated.

Yup' that is the difference between the MacBook Pro's PCIe drive and the spinning 5400rpm HDD in the iMac.

An SSD in a USB 3.0 enclosure will get you up somewhere around 400 to 500MB/s. Not quite as fast as the MacBook Pro's PCIe, but it will be a noticeable difference at somewhere around 5 or 6 times faster than the iMac's stock 5400rpm drive.

Good morning and thanks again.

The firm den.thed linked has a UK partner:

https://www.megamac.com/collections/owc

I have an OWC SSD in my 20212 MBP and it is approaching its second birthday with zero issues. Crucial is good too. Samsung seems to have lost their once-gilded reputation with SSDs in Macs and, on our side of the Pond, their phone support services fall between dismal and abysmal.

Have you looked at what replacing the internal drive entails? This enlightening video is from OWC's US support site:

https://eshop.macsales.com/installvideos/imac_21inch_late_2012_ssd/

I asked a respected local service provider what his shop charges for working on "sealed" iMacs like yours. He said opening and closing any Late 2012 or new iMac is going to be a two hour labor charge at the equiv of £57 or €63 per hour. He said if his techs get through sooner, he reduces the time charged to 1.5 hours but it has never been less.

If you are comfortable with the steps needed to do it yourself, by all means carry on. I want you to be sure you know the scope of the work up front. I've never enjoyed surprises once I get a computer open!!

I'm late to this party but I'll add my 2¢ worth. A 2012 machine with 16GB should be doing better than yours. It should be slow to boot and launch applications but once running it should be pretty smooth unless you are running high resource apps. Google Chrome is one and with lots of tabs open it will eat RAM like I eat M&Ms (which is why we dont' keep them around the house). But still, your read/write speeds to seem to indicate an issue. Given the age it could well be your drive is marginal.

I can say from experience that the 2012 has life left in it if you are willing to boot it from a USB 3 external with an SSD. I'm a huge fan of OWC (macsales.com) drives because they are built like tanks. But here at work we are using a lot of Sabrent equipment and for the price they are quite good. Tech support likes these drives because they are essentially covered docks. It is easy to load in a 2.5" or 3.5" drive - we use them for creating images for the various computers on campus. As for the SSD itself, I'm a fan of Crucial Tech's drives.

I was confused because the iFixit kit you linked is for replacing the internal drive. Note the "adhesive strips" and "opening wheel" in the "what's included" list. That's part of the "surgical kit" needed for opening and closing the computer.

The enclosure included in that package is only UPS 2.0 which will create a huge performance drop compared to your current 3GBps hard drive because USB2 can only reach a max transfer rate of less than 0.5GBps. The "external" solution MUST have a USB 3 drive or performance will go down badly.

I'm a long-time OWC customer and all our externals are now theirs. I slogged through issue after issue with "name-brand" drives thinking they were quality bits of kit but they always disappointed. Were I in your position I would be looking at these two OWC products:

USB3 Enclosure: https://eshop.macsales.com/item/OWC/MEPMU3ES/

with the optional A/C power adaptor https://eshop.macsales.com/item/Other%20World%20Computing/MOTGPWR/

6GBps SSD: https://eshop.macsales.com/item/OWC/S3D7E6GT1.0/

MegaMac lists the same SSD in their site. Check with Megamac about the enclosure. The Akitio enclosures look very similar to OWC's Mercury Elite Pro Mini and they may be making bespoke enclosures for OWC. If that is the case, I am fine with the Akitio.

1. That is the wrong iMac model to run Google Chrome, Microsoft, and Adobe products on.
2. There is no Time Machine Backup to protect your data. Back up your Mac with Time Machine - Apple Support
3. Running from an SSD would help. However, instead of risking an internal transplant you can simply Install macOS on an external USB 3.0 SSD and run from that.

Yes, the USB 2 enclosure is, as they say, a "dealbreaker." It was provided in the kit solely for a one-time transfer of the data for an old internal drive to a new drive. A good way to shift obsolete hardware out of inventory.

The external USB SSD option requires no disassembly of the computer so you would be wasting money on anything that includes disassembly tools. Installing an SSD in an OWC enclosure requires only a small Phillips screwdriver. Then you plug it in.

I'm glad that helped. The drive speeds are similar in the second report. Now I am not sure why unless the hard drive is showing its age.

If you give us a rough idea where your are in the world. we can see if we can supply some vender information for reliable and tough external drives. You probably don't want your boot drive in a cheap enclosure whose primary design/performance requirement was to go on sale every other weekend!

Another great upgrade option, comes from > https://eshop.macsales.com/shop/ssd/owc/imac/2012-early-2013

Hey dwb!

Thanks for the tip on the Sabrent drive. I caught it on sale for 19.99 and it is arrived Friday. I have two dead iMacs and two dead MBPs with SATA drives that need their drives removed and archived. That is the perfect tool. I also have a couple of pulled drives with some old backups.

The drive's included A/C power supply is a happy bonus. I pay US$10 extra for the ones I buy for our OWC Mercury Elite Pro Minis to make them self-powered

Awesome job, Allan!