Email Facebook Twitter Reddit
Apple is ending support for older Mac hardware in new releases of macOS. Here's how to run modern macOS on older Macs using OpenCore.
A few years ago, enterprising modders and hackers began working on software tools that would allow macOS to be installed on standard PCs. This group of enterprising individuals, known as the Hackintosh community, have found a way to modify the macOS installer to allow macOS to be installed on standard Intel-based PCs.
The idea is that you can use macOS without paying for a new Apple Mac, saving you money.
There are several development groups creating Hackintosh installers for third-party computers, and by far the most popular of them is OpenCore, an open repository on acidanthera's GitHub page.
OpenCore is essentially a boot loader that installs and modifies boot blocks on a PC's storage device to allow multiple operating systems to run.
Bootloaders work by installing a small piece of code onto a computer's disk along with one or more operating systems, which, when launched, prompts the user to select an OS to run. After selecting the OS, the bootloader moves to the selected OS and starts launching.
Usually a little firmware trick is also required – in the case of modern PCs or Intel Macs, UEFI (Unified Extensible Firmware Interface) is used.
One of the big benefits of creating a Hackintosh or using OpenCore is that it allows you to run new versions of macOS on older Macs or PCs. So if you have an old Mac, you can use it to run the modern version of macOS.
Apple stops supporting older Macs with new versions of macOS every few years, so new versions won't work on older Macs.
Specifically, macOS Sonoma and Ventura will not work on any Mac released since about 2012 or earlier, and certainly not on Macs released since 2008 or 2009.
Warnings
OpenCore is currently still under development and not supported. So be aware that it may become unstable, causing you to lose your hard drive and destroy all your data.
In any case, be sure to take a full backup of your Mac or PC before attempting to use OpenCore.
Also be aware that in some cases, using a modified version of the Apple macOS installer in the US may be illegal under US law. Specifically, the Digital Millennium Copyright Act (DMCA), passed in 1998 at the height of the dot-com boom, prohibits modification of any compiled binary copyrighted software that is available from commercial vendors.
Therefore, using a modified version of the macOS Installer, any software that modifies it, or any modified version of macOS installed may violate the DMCA.
For these and other reasons, we do not recommend installing or using OpenCore or its related utilities.
This article is for informational purposes only. Install and use OpenCore at your own risk.
Getting started
We will not go into all the details of how to install OpenCore directly because there are plenty of other tutorials for this on the internet.
This is a complex process. There are several GitHub pages and repositories with instructions and tools for installing and using OpenCore.
A much better way to run new versions of macOS on older Macs (if you choose to do so) is to use Dortania's OpenCore Legacy Patcher (OLP).
OLP allows you to install and run versions of macOS back into Big Sur on Intel-based Macs from 2008 onwards. This is achieved by creating a custom macOS installer for a specific old Mac with all the correct drivers and hardware-related code.
It fixes and creates a new installer with all the included changes that are installed during installation.
When you run the patched macOS installer on your Mac, it knows how to install macOS on the old machine, even if Apple doesn't support it.
As a result, you can install any macOS from Big Sur to Sonoma on older, slower, less powerful Macs.
You may want to use an older Mac with at least 4GB of RAM, but 8GB or more is best. Both macOS Sonoma and Ventura really don't run very well on Intel Macs with less than 16GB or 8GB of RAM.
Downloading
To use OpenCore, you'll need an older Mac and a 16GB or larger USB flash drive. You'll create a macOS installer on a USB flash drive, plug it into your old Mac, then boot from it and run the macOS installer from there.
OpenCore only supports clean installs and upgrades of macOS.
To create a USB installer, you need to read dortania's OpenCore installation guide, linked on the GitHub home page. There is an OLP manual that details how to get started.
There is also terminology and a “Supported Models” page.
Keep in mind that using OLP and creating an installer for your Mac involves several steps. You need to read the instructions carefully as this is not a simple one-click installation.
On the main start page, click Download and build the macOS installer. From there, go to the episodes page by clicking“Release of OpenCore Legacy Patchers Apps”
The current version of OLP at the time of writing this article is 1.1. Scroll down and under Resources, click AutoPkg-Assets.pkg and OpenCore-Patcher-GUI.app.zip. The source code is also available in .zip and .gzip formats.
Or you can clone the entire repository to your disk using git.
Once you have all the OLP resources, you will need to unzip them into your Mac's storage. You'll also need a copy of the Apple installer for the version of macOS you want to install on your old Mac.
Any local copies of macOS installers you plan to use must be in the /Applications folder at the root of your Mac's startup drive, otherwise OLP won't be able to find them.
If you don't have a copy of the macOS installer you want to use, fear not—OLP knows how to download it for you if you want it.
Building the Installer
Once you have assembled and extracted all the software, run Open the Legacy Patcher application.
You will be presented with one window with four buttons:
- Create and install OpenCore
- Create macOS installer
- Root patch after settings
- Support
Don't click the Support button – it's a joke and if you do, you'll get rickrolled. OLP is not currently supported.
Next, click Create a macOS installer. This gives you three more buttons:
- Download macOS installer
- Use existing macOS installer
- Return to main menu
Select a macOS installer.
Use these buttons to either select an existing macOS installer application or download a new one from Apple's servers.
If you choose to download the macOS installer, you will be prompted with two or three more windows asking you to select the version of macOS to download and whether it is supported or not.
If you're using OLP on an older Mac that you're about to patch or install on, you'll be told whether the computer is supported by the selected macOS installer.
If not, you can run OLP on a modern Mac and then install it on an external USB drive – as long as OLP knows which model of Mac you want to install on. You can also view all supported models in the Preferences window in the pop-up list at the top:
Set your target Mac model in the Preferences window.
Once downloaded or installer installation, connect the USB drive to your Mac and continue.
Note: OLP will erase the entire USB drive and create a patched installer on it, so make sure there is no data on the USB drive that you want to keep before proceeding.
In the next two steps you will choose which installer to use and which USB drive to burn it to. BSD USB disk device names are used in conjunction with the manufacturer's disk description built into the USB drive's firmware.
Select the local macOS installer under /Applications that you want to use.
Select the USB drive you want to burn the installer to and continue. Once you click which USB drive to use for the installer, the flashing will begin.
The progress window will indicate the blinking status and whether the USB drive was created successfully or not.
Select the target USB drive to burn the installer to.
Build
Once your USB drive is flashed, you will need to go to the “Build and Install OpenCore” page (i.e. – “ASSEMBLY”).
On the BUILD page you are immediately warned that OpenCore builds are hardware dependent, and if you are not building on the Mac you intend to install on, you will need to select the target Mac model in Settings:
Warning:OpenCore configurations vary by hardware. If you are creating OpenCore for a model other than the one you are currently using, it is absolutely necessary to select the appropriate model in the settings.
Once everything is ready, click the Build and Install OpenCore button in OLP to start building OpenCore itself. You will receive a notification when the construction process is completed.
When OpenCore finishes building, you will receive a warning with a Install to disk button. Click on it to select the drive and volume on that drive to install OpenCore.
Installing macOS
The next page of instructions, linked at the bottom of the previous page, is called ” Download OpenCore and macOS. Click on it to go to the next step.
To restart, make sure the built-in USB flash drive is plugged into your old Mac, restart your computer, and hold down the Option key on your Mac keyboard. This boots the Mac into the EFI boot menu.
From there, select EFI Boot, which has an OpenCore icon with a disk icon:
EFI Boot Menu.
Click the arrow button to boot from the USB flash drive.
From there you will see a similar OpenCore picker. Select Install macOS Sonoma or whatever macOS flavor you've created for installation to begin the process.
You can also build the installer to use verbose mode so you can see details of what's happening during installation.
Downloading macOS
After installing macOS, restart your computer to load macOS. Run OLP again.
The final page of the “After Installation”instructions tells you that you can now do several things. You can:
- Boot without a USB drive
- Boot seamlessly without a boot picker
- Applying volume patches after installation
To use the first option, follow the instructions on the post-installation page. Essentially, you need to run OLP from the newly installed drive, change its settings, build OpenCore again, install OpenCore on the internal drive, and reboot one last time using the Option key.
By selecting the recently patched macOS on your internal drive, you can boot to it in the future without the need for a USB drive.
To use the second option (smooth download without download selector), you need to run OLP again, go to its settings and disable Show OpenCore Bootloader.
You will have to rebuild OpenCore again, and after that you can display the OpenCore selector by holding down the Esc key while clicking on the EFI boot volume in the Options menu. screen (i.e. by holding down the Option key while rebooting).
The last option (Apply volume patches after installation) is only necessary if you did not create the USB flash drive from OLP. If you have done this, this step will be completed automatically.
You currently have a fully installed and patched version of macOS running on your legacy Mac.
Additional resources
There are many tutorials online on how to use OLP to install a new version of macOS on legacy hardware. Some YouTubers have tutorials with varying levels of detail on installation.
Sean from Action Retro has a fifteen minute video and Mr. McIntosh has a more detailed, albeit forty four minute video.
Sean uses OLP to install Sonoma on a 2012 MacBook Pro with only 3GB of RAM.
Also, keep in mind that Apple just released macOS Sonoma 14.1, and apparently there are some potential issues with 14.1 and OLP 1.1. So be careful using this combination until the OLP update is released.
The OpenCore Installation Guide contains quite a bit of technical information, including issues with various integrated GPUs on various older Macs, as well as details on how the OpenCore boot process works.
It also has pages dedicated to ACPI (Advanced Configuration and Power Interface) as defined by the UEFI forum. As explained on the OLP ACPI page, ACPI uses tables that identify the devices present on the computer, and the Mac is very finicky about how these devices are represented and their descriptions.
Intel also publishes a book on ACPI.
Many of the fixes that OLP applies involve updating these tables to match older hardware devices that Apple no longer supports.
There are also issues related to kernel address space layout randomization (KASLR) that OLP tries to mitigate and which can vary from Mac to Mac.
OLP builds on another acidanthera project, Lilu, which is an open source kernel extension patch library (KEXT).
Be sure to take a look at the Settings window, as OLP offers a huge range of configuration options.
OLP is great software that can keep modern versions of macOS running on your older Macs for years to come if you want.
