I have a late 2009 27inch iMac I bought when I retired.
It has a 3.06 Ghz Intel core 2 Duo, 16 GB 1067 MHz DOR3 memory and runs High Sierra 10.13.6.
Other than browser issues due to them no longer being supported, it works perfectly and it would not only be extremely wasteful to dump it but also extremely costly to replace it (as a pensioner).
Is there anything that can be done technically to enable it to run later operating systems and extend its life?
iMac
Depending on how you utilize this old iMac, you could install Linux Mint on it which would give you an up to date non-Apple OS which would have access to all the popular third party browsers such as Firefox, Google Chrome, and Vivaldi as well others. Most Linux distributions also have access to a lot of free & open source apps within their distribution's software repositories such as the LibreOffice suite mentioned by another contributor. There are also open source photo & video editing apps, drawing apps, and even some games and email client apps if you don't like accessing your email through a browser.
Linux Mint is one of the easiest Linux distributions to install & maintain and will usually just work with older Macs. A co-worker installs Linux Mint onto our organization's old Macs and gives them out to the less fortunate in our community. It is a great way to extend the useful life of an old computer, but it does require you to learn a new OS. You can easily take Linux Mint for a test drive by using the "Live Mode" from the Linux Mint's USB installer, however, it will perform very slow this way due to the extremely slow USB2 port on that computer (and the slow USB stick), but it will give you an idea what Linux Mint looks like without actually installing it. You could also install Linux Mint to an external USB drive to test it further.....it will still be slow booting from an installation on an external drive, but it may not be too bad for testing and it won't affect your current macOS internal installation & setup.
If you decide to install Linux Mint to the internal drive, then make sure you back up any important files to external media formatted so that any OS can access the data (basically have an external data drive holding your important files). Linux cannot access a standard macOS backup from Time Machine and some other third party apps. And make sure you first create & test a bootable macOS 10.13 USB installer so that if you change you mind and want to return to macOS that you have a way of reinstalling macOS (currently Internet Recovery Mode for older versions of macOS may no longer be available, so a bootable macOS USB installer is critical).
Linux is not for everyone and does require you to learn a new OS, but there are several ways of trying it out which won't affect your current macOS installation (as long as you do not erase the internal drive anyway).
The biggest problem for a computer this old is that the hard drive may be wearing out or even failing depending on how heavily you used this computer during its life.
Depending on how you utilize this old iMac, you could install Linux Mint on it which would give you an up to date non-Apple OS which would have access to all the popular third party browsers such as Firefox, Google Chrome, and Vivaldi as well others. Most Linux distributions also have access to a lot of free & open source apps within their distribution's software repositories such as the LibreOffice suite mentioned by another contributor. There are also open source photo & video editing apps, drawing apps, and even some games and email client apps if you don't like accessing your email through a browser.
Linux Mint is one of the easiest Linux distributions to install & maintain and will usually just work with older Macs. A co-worker installs Linux Mint onto our organization's old Macs and gives them out to the less fortunate in our community. It is a great way to extend the useful life of an old computer, but it does require you to learn a new OS. You can easily take Linux Mint for a test drive by using the "Live Mode" from the Linux Mint's USB installer, however, it will perform very slow this way due to the extremely slow USB2 port on that computer (and the slow USB stick), but it will give you an idea what Linux Mint looks like without actually installing it. You could also install Linux Mint to an external USB drive to test it further.....it will still be slow booting from an installation on an external drive, but it may not be too bad for testing and it won't affect your current macOS internal installation & setup.
If you decide to install Linux Mint to the internal drive, then make sure you back up any important files to external media formatted so that any OS can access the data (basically have an external data drive holding your important files). Linux cannot access a standard macOS backup from Time Machine and some other third party apps. And make sure you first create & test a bootable macOS 10.13 USB installer so that if you change you mind and want to return to macOS that you have a way of reinstalling macOS (currently Internet Recovery Mode for older versions of macOS may no longer be available, so a bootable macOS USB installer is critical).
Linux is not for everyone and does require you to learn a new OS, but there are several ways of trying it out which won't affect your current macOS installation (as long as you do not erase the internal drive anyway).
The biggest problem for a computer this old is that the hard drive may be wearing out or even failing depending on how heavily you used this computer during its life.
Mostly you just need a more modern Browser than Safari on Mojave, or High Sierra like Firefox or Brave.
https://www.mozilla.org/en-US/firefox/83.0/system-requirements/
Firefox 83.0 System Requirements (mozilla.org)
Opera…Thanks
https://www.opera.com/download/requirements
Opera system requirements | Opera
Thanks to dialabrain…
Firefox 115 is now the current version. runs in High Sierra.
https://www.mozilla.org/en-US/firefox/new/
Look into the Free LibreOffice, it handles MS Office files like Word & Excel, & Page Layout…
Thanks to Matti Haveri…
https://discussions.apple.com/thread/254698315?answerId=258771288022#258771288022
LibreOffice 7.0.4 works in macOS 10.11 and 10.14.
If it still works acceptable well, there's no reason to dump it.
You may need a more modern browser such as Firefox, but other than that it still likely does for you just what it did when new.
Surf safely, follow the usual precautions about malware and spam and enjoy.
There are plenty of "modern" apps that will still run on your machine per the earlier post.
If not "refurbished" by Apple or MacSales you may be buying trouble.
Keep it as a backup ... insurance of a sort. You'd be surprised at the number of post here about a Mac going down and the problems associated with no backup computer.
Apple don't have any suitable refurbished iMacs at the moment. I purchased a 27' Retina 5K running Ventura from Tech.Trade who have over 1500 reviews on Trustpilot and an average score of 4.9 so I think they should be OK. Interestingly, in addition to their own 12 months return to base warranty, there's a manufacturer's limited warranty for 1 year & technical support (phone consulting) for 90 days, so I'm thinking it's either pretty new or is Apple refurbished because you don't usually get that.
No, sorry.
Thanks for the replies. I've decided to buy a refurbished iMac with Ventura to solve my problem but I'll keep my existing one for additional storage - maybe even a web server if I can figure out how to do that!
Deleted ... duplicate partial post
And, yes, I intend to keep mine as a backup and additional storage. I have Time Machine so it shouldn't be necessary but belt and braces!
+1:)
Thanks but I've now taken delivery of a refurbished iMac and am in the process of transferring my files.
"Apple don't have any suitable refurbished iMacs at the moment"
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That just means users are keeping their old Macs just like you can.
You do you and all will be good.
Can an old iMac's life be extended?
