Imac 2015 best OS

Dear friends,


I have an Imac from 2015 running with OS Monterey. It has a bit of a slow startup, and in general slightly slow even after a clean install. Maybe it would be wise to downgrade to an older system? I was trying to gather some more information about which OS to use. Anyone can help? Thanks.


2,8 GHz Quad-Core Intel Core i5

8 GB 1867 MHz DDR3

Posted on Jul 1, 2023 6:50 AM

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Posted on Jul 1, 2023 8:56 AM

Based on the CPU speed, you seem to have an iMac (Retina 4K, 21.5-inch, Late 2015). Is that what the machine shows in the About This Mac dialog in the Apple () menu?


That machine came with a 1 TB hard drive, a 1 or 2 TB Fusion Drive, or 256 or 512 GB of flash storage. If it has a hard drive or Fusion Drive, you might be able to improve startup and application launch times by quite a bit … by replacing the hard drive or Fusion Drive with a SSD.


A Fusion Drive combines a hard drive with a tiny amount of flash storage, but on Late 2015 iMacs with 1 TB Fusion Drives, the amount of flash is especially tiny: 24 GB. Even just putting your computer (with 8 GB of RAM) to sleep would take up a third of that, or require shuffling of data to the slow hard disk component of the Fusion Drive.

https://9to5mac.com/2015/10/13/retina-imac-fusion-drive-flash-lol-are-you-serious/


Upgrading the internal drive with a "blade" SSD (if possible) or a 2.5" SATA notebook SSD would be an intricate operation involving fairly major surgery on your iMac. You could, instead, get an external USB 3 SSD, set it up, and then use it as your new startup drive.

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Question marked as Top-ranking reply

Jul 1, 2023 8:56 AM in response to joaoteodosio

Based on the CPU speed, you seem to have an iMac (Retina 4K, 21.5-inch, Late 2015). Is that what the machine shows in the About This Mac dialog in the Apple () menu?


That machine came with a 1 TB hard drive, a 1 or 2 TB Fusion Drive, or 256 or 512 GB of flash storage. If it has a hard drive or Fusion Drive, you might be able to improve startup and application launch times by quite a bit … by replacing the hard drive or Fusion Drive with a SSD.


A Fusion Drive combines a hard drive with a tiny amount of flash storage, but on Late 2015 iMacs with 1 TB Fusion Drives, the amount of flash is especially tiny: 24 GB. Even just putting your computer (with 8 GB of RAM) to sleep would take up a third of that, or require shuffling of data to the slow hard disk component of the Fusion Drive.

https://9to5mac.com/2015/10/13/retina-imac-fusion-drive-flash-lol-are-you-serious/


Upgrading the internal drive with a "blade" SSD (if possible) or a 2.5" SATA notebook SSD would be an intricate operation involving fairly major surgery on your iMac. You could, instead, get an external USB 3 SSD, set it up, and then use it as your new startup drive.

Jul 1, 2023 9:29 AM in response to joaoteodosio

Before replacing drives in a computer that Apple did not design for us mere mortals to open, PLEASE post data regarding your current system condition. With proper data we can best advise you witut waiting your money.


History says a slow 2012-2019 21.5" iMac is suffering from the under-spec factory internal mech drive. However, if your computer has a Fusion drive that can be restored to normal function, it wll get write/read speeds well above the SATA SSD internal drive conversion.


To post the data we need, there is a safe, secure way to do that without our playing a protracted game of "20 Questions" with you that could go on for hours or days.


We can quickly and within the confines of these forums help you determine what issues are at play if you use EtreCheck Pro, available here:


https://etrecheck.com/index


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 RAM usage. Etrecheck is the development of a long-serving and trusted contributor here expressly for displaying information in these forums to help us help you. It will not reveal any personal or secure information.


Please see this excellent user tip on posting long text reports like EtreCheck.


https://discussions.apple.com/docs/DOC-250000211




Jul 5, 2023 10:00 PM in response to dialabrain

dialabrain wrote:

Acquiring an inexpensive external SSD and installing Monterey on that then migrating your data would certainly speed up things for you. However, 8GBs of RAM is basically minimal for recent versions of macOS.


This seems to be one of the few 21.5" iMacs where the memory is not just sealed in – but soldered in. While there were 16 GB variants, MacTracker says that there are no memory slots inside.

Jul 5, 2023 8:33 PM in response to joaoteodosio

+1 to dialabrain!


Your Mac can have improved system performance by connecting to an external solid-state drive (also known as an SSD). An external SSD as a startup disk can give your Mac additional performance for system responsiveness, apps, startup, and more.


If you're interested in this solution, this article should help: Use an external SSD as your startup disk … - Apple Community.


Another option is to replace this Mac with a new Apple Silicon Mac: Mac - Apple. You can also use Apple Trade-In to get credit towards a new Mac: Apple Trade In - Apple.


- Jack

Jul 5, 2023 3:32 AM in response to joaoteodosio

FWIW, your report indicates you have no Time Machine backup. You would at least need a Time Machine or other backup system before attempting to downgrade.


Acquiring an inexpensive external SSD and installing Monterey on that then migrating your data would certainly speed up things for you. However, 8GBs of RAM is basically minimal for recent versions of macOS. You might want to think about replacing your Mac. It's already considered vintage and soon to be considered obsolete.

See: Obtaining service for your Apple product after an expired warranty - Apple Support

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Imac 2015 best OS

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