
If you really want to try this, borrow a friend's older Mac and make an installation of 10.9 to an external drive and try booting it on your Mac mini (holding down the option key at boot to boot from the external drive). You're almost in Hackintosh territory here. It's a totally unsupported thing to do and very likely to be unstable. If a machine is sufficiently similar to a previous generation and has enough driver support, it might be technically possible to get a prior version of OS X to boot on it, but it's almost certainly going to require manual tweaking to bypass the system identifier checks that happen. To install this version, you should use the Internet Recovery based installer (or for older models, the recovery discs that came with your Mac).

HOW TO INSTALL OS X 10.9 ON MAC MAC OS X
It's important to note that when installing supported older versions of Mac OS X on a Mac, you can use the standard installers for all versions except for the original OS version that the model shipped with. It shipped originally with 10.10, so that'll be the earliest that you can install on it in any officially supported way. PS: Apple has a support article for this as well, see Use the version of OS X that came with your Mac, or a compatible newer version.Īssuming that you're talking about the latest Mac mini (Late 2014) at the time of writing, you won't be able to install 10.9 on it. Therefore, OS X 10.9 will not be able to recognize your newer machine's hardware.

For this to work, Apple would have to have released an updated version of OS X 10.9, which they have not done. The older versions of the Apple OS X operating systems are not capable of running on hardware yet to be designed.
