Tip - installing OSX via Target Disk Mode

I'm not sure if it is clear, but installing an operating system from Target Disk Mode, necessitates the model and vintage of the Mac to be the same for the host as the target machine. If they are not, drivers that are incompatible may be copied over. Target Disk Mode installs are still useful, obviously if the drive fails. A Universal Installer may sometimes work on a different model, but, the series that do work is not very well documented, and errors such as kernel panics, and other driver errors are much more likely. The Target machine is treated by the installer much as an external hard drive attached to the host machine. Thus a Target iBook G4/933 Mhz machine will not tell the installer from an iBook 1.4 Ghz machine that it is installing on an iBook 933 Mhz machine, and it will attempt to install the software it thinks is needed for the 1.4 Ghz.

You can also use Target Disk Mode to examine another machine's directory health with Disk Utility (using Verify and Repair Disk), as long as that machine is using an older operating system.

Reading that over again, and thinking about it, I realized what you meant. It would seem that some may miss that point even after the bold in red. Instead of saying receiving mode, what you need to do is establish the steps:

1. Put machine A in target mode by holding the T key.

*2. Insert the compatible installer CD for machine B in machine A's optical drive.

3. Tell machine B to go into the startup manager.

4. Connect machine B to machine A.

5. Machine B should now be able to install that operating system on machine B.

* A compatible installer would be a newer retail, up the limits of machine's B hardware or the original installer for machine B which if lost can be obtainable from AppleCare.

In fact what I'm doing is rather intriguing. I installed via target mode 10.5 retail onto a second partition of my iMac 11,3 which can't boot anything older than 10.6.4. My MacBook Pro which dates from 10.4.7 days is now booted off that partition as the iMac is in Target mode.

Obviously the iMac will still never boot off 10.5, but it does show what another approach to target mode might be.

Read, or interpreted, on another forum that the receiving Mac be in TDM.

Thank you mackerm, for this clarification! And thank you a brody, for your follow-up notes!

Used TDM from Mac A -- specs:

Model Name: Mac mini

Model Identifier: PowerMac10,1

Processor Name: PowerPC G4 (1.2)

Processor Speed: 1.25 GHz

Number Of CPUs: 1

L2 Cache (per CPU): 512 KB

Memory: 512 MB

Bus Speed: 167 MHz

Boot ROM Version: 4.8.9f1

Operating System: Mac OS X Leopard (10.5.1)

to install Mac OS X Leopard (10.5.1) from the Mac A DVD,

onto Mac B (which had no OS installed) via its

Startup Manager -- specs:

Model Name: PowerBook G4 15"

Model Identifier: PowerBook5,6

Processor Name: PowerPC G4 (1.2)

Processor Speed: 1.67 GHz

Number Of CPUs: 1

L2 Cache (per CPU): 512 KB

Memory: 512 MB

Bus Speed: 167 MHz

Boot ROM Version: 4.9.1f3

Success! Be well [namaste']

While a valid tip, in practice from OS8-OSX 10.4.11 (so far) I have taken hard drives complete with OS and moved them from computer to computer and not had issues. Admittedly with OSX 10.4.11 my move was from a Quicksilver dual 800 to a dual 1GHz model which is not a radical transition, but there may be flexibility in the OS. I agree though if you were borrowing an Intel Mac as part of a PPC installation you would definitely need to get it the right way around.

Great tip thanks! 🙂

Thanks - really helpful