I recently purchased a brand new 27" iMac that came with snow leopard as the default os. I was wondering if I could use the back up disc that it came with to install it on my old 21" iMac that is 5 years old. I have seen on various forums that the discs that come with computers are machine specific, and thus the result is a message stating that "Mac OS X Snow Leopard cannot be installed on this computer." But I've heard there are workarounds to this. Does any one know what they are? Thanks.
If you have the gray installation CD you probably won't be able to do it because they are machine specific, but its worth a try. If you boot from the CD & it is not compatible with the machine it will just tell you to press the power button to turn off your machine. Then just boot normally & eject the CD, no harm done.