Hi, can this be done? I have an iMac running 10.5.x. I also have 10.8 on a USB drive. I do not need to "upgrade" or keep any of the information on the iMac I simply want to do a fresh/clean install of 10.8. Any guidance will be much appreciated. My experience is with MS not with Apple.
iMac, Mac OS X (10.5.8)
Connect the thumbdrive, restart with the Option key held down, and run the installer. You'll likely need to use the Disk Utility to erase or repartition the iMac's internal drive.
(141830)
With that said the whole installation will run from the thumb drive? Sorry for my lack of know-how, I have a total WIndow's brain.
If you created it with a tool such as DiskMaker X, yes.
If you drag-copied the installer, no.
(141833)
I did not create it with disk maker - simply drag and drop - this brings up another question - will the version of diskmaker that is compatible with 10.5 work to make a "?bootable image?" for 10.8?
DiskMaker X requires at least Lion. Go back to the computer that you downloaded the Mountain Lion installer to and create the thumbdrive there; if you can't do this, you'll need to go through Snow Leopard.
(141835)
The standard (Apple-endorsed) way to do this is to install Snow Leopard from an official Mac OS X installation disc. Once Snow Leopard is installed, you can use the Mac App Store app to download and install the latest supported version of OS X for your Mac model.
You can buy the Snow Leopard installation disc here
http://www.apple.com/shop/product/MC573Z/A/mac-os-x-106-snow-leopard
If Mountain Lion is the latest version of OS X for your Mac model, you can order it here
http://www.apple.com/shop/product/D6377Z/A/os-x-mountain-lion
Your iMac is "mid 2007" or newer, and it has sufficient RAM, it can run the current version of OS X (El Capitan), which is a no cost upgrade from Snow Leopard.
https://www.apple.com/osx/how-to-upgrade/
EDIT: Second link was wrong. I corrected it.
Thanks for that, I was looking for a work around as I have 10.5 installed, and have 10.8 on a USB drive - want to save myself the time and $ and not order 10.6.
iMac 10.5 to 10.8 fresh install
