Just bought MacMini M1, not happy with BigSur can I install Catalina and if so how?

Solution 1:

The minimum OS you can run on an M1 Mac mini is macOS 11 Big Sur.

It will not run Catalina.

Sorry.

Solution 2:

The M1 Mac mini will not run Catalina, due to Catalina being an x86-only operating system, and the M1 Mac mini using an ARM-based processor.

To see which systems are compatible with Catalina, view Apple support article: macOS Catalina is compatible with these computers

Solution 3:

No. macOS Catalina is only compatible with these computers, which do not include any M1-based models.

Solution 4:

Just bought a MacMini M1, not happy with BigSur is it possible to remove BigSur and install Catalina and if so how?

Running an older macOS 10.x on the M1 "metal" is not possible, the hardware required is simply not there. Running an older macOS 10.x on the new Apple M1 processor with macOS 11.x as a host to a macOS 10.x virtual machine guest is likely to be possible soon. I've been using macOS as a host to a number of different operating systems for some time and there's a lot of good software for this. But what I'm doing is more accurately called virtualization, I'm creating an instance of a x86-64 processor that runs on an x86-64 processor for this guest operating system to run on. There are hardware "hooks" in the instruction set to aid this and improve performance. Most virtual machine software requires the host and guest to use the same instruction set to work. Some require more from the host processor in having these virtualization "hooks" to hold on to in order to aid in speed, stability, and features.

Apple made the M1 with these virtualization "hooks" to aid in creating ARM virtual processors for running versions of Windows and Linux written for ARM. This would at best allow a guest instance of macOS "Big Sur" on macOS "Big Sur"

There are emulators in progress that will allow an ARM based host to have a x86 guest. These will not have the same kind of performance as a like-on-like processor virtualization. Apple knew that there would be a period of time where people would need to run x86 software on their new M1 processor so there are "hooks" on the M1 to aid this as well. This is intended to help run software written for macOS on x86 to work on macOS on ARM. Software for x86 that does not require the x86 hardware virtualization "hooks" might be able to run but that means the emulated x86 will be lacking in some way. This would be something like VirtualBox with the emulator mode instead of virtualization mode running on Rosetta2 to run a VM.

I recall seeing people install Windows and Linux on M1 "metal" with some success. It may be possible for these to run an x86 emulator that can host an older macOS x86 guest machine.

There has to be a number of ways to put an emulation layer on the M1 so that some version of x86 macOS can run. The options I'm seeing is some M1 native OS, macOS 11, Windows for ARM, or Linux for ARM, being a host to some x86 emulator, Bochs, VirtualBox, or whatever. But these are all in early development and will not be stable enough for some time. Because this means running an OS on top of an OS there will be penalties for memory, storage, and speed. Given some reports on some attempts to do this there is a potential that such penalties will be barely noticed.

If this is possible now then it's going to be buggy and slow. In time I expect this to be popular among developers, enthusiasts, gamers, and retro-computing types.

Because of how things like this work there may be a working emulator for PowerPC macOS available for M1 before there is any x86 macOS emulator for M1. What does anyone think of running Snow Leopard? Then run VirtualPC to host macOS for intel?