Unable to boot on old Mac

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New member
Jun 26, 2024
I read that Spinrite should be able to run on Intel Macs but I am not sure if the iMac I am trying to use is too old for this (Apple iMac Core 2 Duo 2.0Ghz Mid-2007 running Mac OS X Tiger 10.4). I have created the bootable USB but when I press the Option key while the iMac starts only the internal hard drive is offered to boot from. When I boot into MacOS I can see my USB drive is connected and its contents. Am I missing something here?
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Based on what I learned when I wrote the article below, you may have to boot that Mac from a CD:

Many thanks Scott! Your reply was a real trip down memory lane. First I had to get my now ancient DVD writer reconnected on my Windows PC as lack of use meant that I decided to unplug it internally on my case as my daughter kept bumping into it and opening the caddy which was eventually going to break. I left no SATA cables so I had look at my box of "mixed" spare cables for a SATA cable which of course was a the bottom. Once I reconnected the DVD writer it refused to open the caddy, probably down to my daughter's abuse and the many years without use. Eventually I force it to open and to my surprise it work fine after that. Then again back to reach the end of my cabinet to find virgin CDs which I still had plenty left. I naively tried to burn the .IMG file and it got burned as a .IMG. I downloaded the .ISO and burned that too, again as a file not as a image. Clearly my CD burning skills need to be brushed up! Finally on the third attempt I found isoburn.exe and burned it properly. I loaded the Spinrite CD on the iMac, pressed Option on boot and bingo! Run baby run!!!

PS: Many thanks for the informative posts!