backing up your existing drive is always a good idea before any major work is done to the existing configuration.
If you select, single click, your HD icon on the desktop and then to to File/get Info, it will tell you the size of the drive, space used and the space available. Use that figure to see if you can Clone your HD to the 90Gb drive.
If you can't, all is not lost. More people upgrade without a backup than do, it does not always end in disaster.
To be safe, find the size of your Home folder using the same method and if it will all fit on the 90Gb, just drag the whole folder over to it.
Your Home folder contains all your music, movies, pictures, documents and mail.
If you decide to clone the drive, the clone copy would go onto the external.
With either of those done, if your upgrade goes south, you have all that stuff saved.
When it comes to the upgrade, be sure to choose Archive and Install as the install type. This has been shown to be more reliable for this upgrade.
On some Macs, for some reason, there is only one option available. Format and Install. That is not the way to go. All your data will be erased.
Go not further if that is the only option. Quit the installer and get back with us.
Good Luck
P
In most articles about making the upgrade to Leopard, it is suggested that the entire hard drive be either backed up to an external hard drive or cloned. I only have a 90G external hard drive(that is relatively new, and not nearly filled to capacity) which does not seem to bee sufficient to back up my 250G hard drive, but how do I determine if it is? If I do not back up my hard drive, and I have a problem with the Leopard update, can I use the Tiger discs that came with my Intel iMac to reboot? Also, if I clone my existing hard drive, where do I create the clone?
Thanks in advance

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