Hack Your Mac?

[richmond62]

Or, more accurately, "Hack My Mac" . . .

So:

1. I notice that my 2015 iMac 27" retina thingy is fairly glacial with MacOS 12 Monterey.

2. I have 2 2009 Polycarbonate iMacs, both running MacOS 10.7 'Tired Lion'.

"Little Birds" have told me I can upgrade my 2015 iMac to MacOS 13 Ventura, and my 2009 iMacs to MacOS 10.9.

Has anyone ever done this, and:

1. Is it relatively easy?

2. Am I risking hosing my machines so they stop working altogether?

[tperry2x]

[me; keeping quiet at the back of the room, as I know you won't like my answer]

[richmond62]

Don't keep quiet . . .

I promise not to be abusive in this thread.

[tperry2x]

Haha, well - I was only going to mention that I'd recommend going back a few versions if anything.
The thing is, the OS with which the Mac shipped with is generally what it was spec'd out for. Sure, you can upgrade a few versions - but there comes a point when the newer MacOS builds are better targeted to newer hardware.

So, while Apple make it possible to update your mac for quite a long time, it's no surprise the software becomes a burden on the available hardware.

I'd probably recommend going back to anything pre-Monterey on most macs that aren't very recent *. This will make it feel a lot snappier and will mean it's also a good candidate for testing on. You can still run 64-bit stuff, and if you went back as far as 10.14, you can run 32-bit intel apps as well.

*assuming you aren't doing anything that would give you security concerns with it online.

That's entirely up to you of course, just my inane (insane?) ramblings.

[OpenXTalkPaul]

This is sort of an area of expertise for me...
I've been hacking macs for over three decades and have done all sorts of crazy things like flashing Mac Video card roms onto the generic PC equivalent Video Card, modding ATX PSU to power PowerMacs (saved a lot of money with these hacks) and I built my first Intel Hacintosh before Apple released their first consumer MacIntel.

I also recently used OpenCore Legacy Patcher to update my now-unsupported iMac 2015 to Sonoma.
I'm quite happy with the performance, but this particular Mac is a retired graphics workstation with 32GB RAM and Radeon 4GB video card and (most importantly) an M.2 Solid State Drive. I think that probably makes all the difference. if your Mac has like only an older integrated video such as Intel's HD4000 and only 4GB or RAM or some weak-ass configuration like that, then you're probably not going to be too happy running on much newer macOS versions, even though Legacy Patcher would let you try it even on a 15yr old Macs.

The way OpenCore Legacy Patcher works is it displaced/takes over for the 'boot camp' UEFI boot loader with OpenCore (which is a great multi-boot boot-loader for general use, that just happens to come from the Hackintosh community).
The Legacy Patcher version is meant for older unsupported 'real' Macs and it takes care of a lot of the setting-up automatically so you don't have to know much, it will even download a macOS installer and make a bootable USB flash-drive or SD card for you. The things it patches are like drivers for hardware that Apple has dropped support for, mostly its reinstalling drivers and related files from earlier versions of macOS, which might be needed for your Video Card, your Wifi or Ethernet chipset, or Sound chip to work again, depending on the model.

Anything Mohave and above *officially* requires a GPU that is 'Metal' compatible (in Win world that translates to DirectX 11 compatible IIRC), I think Ventura and Sonoma officially require 'Metal2' video (I think that translates to DirectX 12 or 13). If you have a MacPro tower with replaceable video card, you'll probably want to stay away from buying an NVidia card because Apple cut support for Nvidia entirely (some sort of strained relationship there). MacOS will however boot with a basic VESA / Framebuffer driver without any hardware acceleration, but that's not really useful (except when first building your Hackintosh)

If your SSD or HDD is already formatted as APFS then you can easily live-repartition the drive and install the newer macOS on a new partition to test it out (my iMac now has a Mohave and Sonoma dual boot setup), or you could install to another spare drive (likely in an external USB enclosure if it's an iMac). One thing to note is earlier macOS like Mohave won't recognize newer macOS volumes formatting, Finder will give a message to that effect on startup (it's the same as if you had a Linux partition in a Ext4 or other format that macOS doesn't have built in support for).

[OpenXTalkPaul]

I should add that ANY computer would benefit from replacing traditional rotating platter hard-drive with a Solid-State drive, specially the new NVMe drives. I put a basic SSD in an old Core 2 Duo (running Snow Leopard) and the thing FLYS!!! I'm thinking of putting one in my old MDD G4 now (although that would max out at ATA133 speed unless I put it on a PCI card).

[tperry2x]

I put a basic SSD in an old Core 2 Duo (running Snow Leopard) and the thing FLYS!!! I'm thinking of putting one in my old MDD G4 now (although that would max out at ATA133 speed unless I put it on a PCI card).

I'm sure you know, but just watch out for trim support with earlier MacOS if using SSDs.

[richmond62]

Well, well, well: I seem to have ended up with 2 advisors at different ends of the spectrum.

My main interest at the moment is trying to get a 2009 iMac that, in theory, maxes at MacOS 10.7 up to MacOS 10.9.

[OpenXTalkPaul]

I put a basic SSD in an old Core 2 Duo (running Snow Leopard) and the thing FLYS!!! I'm thinking of putting one in my old MDD G4 now (although that would max out at ATA133 speed unless I put it on a PCI card).

I'm sure you know, but just watch out for trim support with earlier MacOS if using SSDs.

I'm not real worried about efficiency on this particular machine, or wear and tear on the already well-used old SSD that I put in it. Anyway the only things on that drive is the OS and some of the Apps so there shouldn't be much block erasing/rewriting on that drive. For more storage I have several old HDDs in the thing as well, it's one of my garage computers .

[OpenXTalkPaul]

Well, well, well: I seem to have ended up with 2 advisors at different ends of the spectrum.

My main interest at the moment is trying to get a 2009 iMac that, in theory, maxes at MacOS 10.7 up to MacOS 10.9.

OpenCore can boot as far back as 10.4.10/11 (first X86) Tiger (theoretically, I've never used it for that myself), but the OC Legacy Patcher project that makes things easy seems to concentrate on newer OSes. I'm not sure if there was something similar for macOS older than 10.13 High Sierra.
If your iMac officially maxes out at 10.7 then it may be because the GPU is dependent on a 32bit Kext (kernel extension). Does it have an Nvidia 7300 or an Intel GMA X3100 graphics maybe? If so you might be S.O.L. trying to go beyond 10.7, because 10.8 allowed only 64bit Kernel (EDIT: this is incorrect, it seems there IS a way to force boot 32bit kernel stuff)

[OpenXTalkPaul]

It would help to know the specs of this 2009 iMac, it might be Nvidia 9400m (Shared Memory Video) or 120 GT.
2009 probably has a good shot of going up to 10.8 at least, there was an Mountain Lion 'ML Patcher' https://osxdaily.com/2013/04/20/mlpostf ... rted-macs/

Oh it looks like there was a 2.0 version that patched to 10.8 through 10.11:
https://osxhackers.net/macpostfactor/

I also just found this collection of patches: https://parrotgeek.com/npf/

https://dortania.github.io/OpenCore-Leg ... .html#imac

The model identifier numbers like iMac 9,1 or iMac11,1 can be really important to making unsupported things work (which can be spoofed to trick the OS).
EveryMac.com is great for looking up the official details: https://everymac.com/systems/apple/imac ... specs.html

[OpenXTalkPaul]

It looks like you might actually be able to upgrade the video card in some of those iMacs, but it doesn't seem like a very easy task to accomplish as it may require a dremel / heatsink mods as well as software mod, but apparently people have gotten some of those iMacs up and running with MacOS 11+
https://forums.macrumors.com/threads/20 ... t-17425857

Impressive for a now-15 yr old Mac really. The best I ever had from a Mac was about 10 years worth of OS/updates with the highly upgradeable PowerMac 9600 (from like 1997 to 2007). It came with System 8.6 and ended running OS X 10.4.x thanks to some clever Mac hackery (and some used Mac Sales Co. sponsorship) and various upgrades on my part (G4, ATI 9200, and 12 RAM slots filled, USB 2.0/Firewire card). It actually still runs well (although it now has a less-good PMac7300 motherboard after screwdriver related mishap) but I put it away in storage a couple of years back. The thing is so thick and weighs like a half a ton due to its steel frame, lol. They don't make like that any more.

[OpenXTalkPaul]

One more link I had open in a tab, this GitHub Gist is a nice little links guide page to various older Macintel models and what they support (incl. unofficially):
https://gist.github.com/wolfiediscord/d ... ericks-109

According to that a 2009 iMac should be natively compatible with 10.9 (and probably up to El Cap 10.11) so you just need to grab a copy of the .dmg and make a boot installer USB drive, you may also have to set the Mac's clock (you can set it via the terminal in while booted in the installer) backwards a decade or so before you try installing, otherwise it will fail during install due to expired authentication certificates on the .pkg files (or find or make a custom install dmg with this stuff stripped out).