Apple Event: May 7th at 7 am PT
I upgraded my late 2015 iMac to have 32 GB of memory, up from eight. I thought when I started it up again it would run faster on start up, but it did not. I am not sure what else to try. There is lots of room on, the hard disk for storage and I really mostly use it to get on the Internet and do some word processing.
Does that iMac have a mechanical hard drive? Or a 1 TB Fusion Drive? (For Late 2015 Macs, the 1 TB Fusion Drives had a very skimpy 24 GB of SSD space, down from the 128 GB that Apple had used in previous years.)
If either is the case, you might benefit from getting an external USB 3.0 SSD and using it as your startup drive. (The 2015 iMacs support USB 3.0, but not Thunderbolt 3.)
A SSD could help to make the machine start up faster and launch applications faster. It wouldn't do all that much to change the speed of working with word processing documents or Web sites once you had booted the Mac and had started up the applications.
Does that iMac have a mechanical hard drive? Or a 1 TB Fusion Drive? (For Late 2015 Macs, the 1 TB Fusion Drives had a very skimpy 24 GB of SSD space, down from the 128 GB that Apple had used in previous years.)
If either is the case, you might benefit from getting an external USB 3.0 SSD and using it as your startup drive. (The 2015 iMacs support USB 3.0, but not Thunderbolt 3.)
A SSD could help to make the machine start up faster and launch applications faster. It wouldn't do all that much to change the speed of working with word processing documents or Web sites once you had booted the Mac and had started up the applications.
What screen size? Entry-level 21.5-inch iMacs made between 2012 and 2019 shipped with slow and under-spec 2.5-inch laptop-class mech hard drives that were were demonstrably SLOWER that drive ins entry-level 2011 iMacs. No amount of added RAM can make this drive any faster.
I agree 110% with Servant of Cats' assessment and recommendations assuming you have the entry level iMac. However both of us are working with a minimum of tech detail from you combined with "slow iMac" history here. If your computer shipped with with an optional storage upgrade (Fusion or SSD) and is still slow, something completely different could be at play.
We do not know your actual hardware config and drive performance data. If you want a machine-specific, data-driven evaluation in this setting where we can neither see nor touch your computer, please post an EtreCheck report. We can quickly and within the limitations of these forums help you determine what issues are at play without our playing a protracted game of "20 Questions" with you that could go on for days.
EtreCheck Pro is available here:
The free version will do nicely for this purpose, although the app is worthy of our financial support.
We can see hard data about drive performance, software issues and interferences, and RAM usage. Etrecheck is the development of a long-serving and trusted ASC contributor. It is a reporting app, not a "fix-it” app, expressly for displaying information in these forums to help us help you remotely. It will not alter your computer nor reveal any personal or secure information.
Please see this excellent user tip on how to post long text reports like EtreCheck's into a forum response:
How to use the Add Text Feature When Post… - Apple Community
"Entry-level 21.5-inch iMacs made between 2012 and 2019 shipped with slow and under-spec 2.5-inch laptop-class mech hard drives"
That's not correct - SSDs were available as a paid option on iMacs since at least 2013.
Allan Jones wrote:
If your computer shipped with with an optional storage upgrade (Fusion or SSD) and is still slow, something completely different could be at play.
For a late 2015 iMac, a 1 TB Fusion Drive with only 24 GB of SSD space might not have been much better than a mechanical hard drive.
If the OP has a 2015 iMac with a 1 TB Fusion Drive, upgrading RAM from 8 GB to 32 GB could even have caused that Mac to become slower in going to Sleep and waking from Sleep. I remember that one Mac news site pointed out that with only 24 GB of SSD space, there would not be enough space to store a complete snapshot of RAM on an upgraded Mac. The Mac would be forced to use the mechanical disk.
By "entry level," I meant with no options. If you have a better term for that, I'm open to suggestions!
Lowest-priced model at checkout.
All this is speculation. OP might well have chosen SSD over fusion. Wait it out?
Thank you, servant of cats! I am not sure what that is, but I will look it up and see if that helps. I really want to keep this computer going as long as I can.
iMac late 2015 runs slow even after memory upgrade. What else should I look at?
