iMac Update Version 1.0 was released September 2, 1998 and is only for installation on the original Bondi blue iMac, and only if it is running Mac OS 8.1.
Hardware Required: Original iMac (Revision A)
Note:The iMac Update 1.0 is no longer available from Apple Software Updates sites.
Important: iMac customers who are using Mac OS 8.5 or later should not install this update and should review article 58174: "iMac: When to Install Available Updaters" to determine if they should install iMac Update 1.1.