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OS X was not released at that time, so it would have been System 8 or System 9...

Edit: Too slow it would seem! 😉
 
The earliest came with 8.5, and the last of the colors came with 9.1

However, if you buy one used nowaday's it very well could have OS X on it.
 
only the last revisions came with an installation CD for OsX.
I bought mine in october 2001 with Os 9 installed as default operation system installed, in the box was also an installation disk with Osx on it.
My father had bought a blue dalmation in februari of the same year that only came with Os9.
 
only the last revisions came with an installation CD for OsX.
I bought mine in october 2001 with Os 9 installed as default operation system installed, in the box was also an installation disk with Osx on it.
My father had bought a blue dalmation in februari of the same year that only came with Os9.

Yep, I'm 'bout positive that you could get the last revisions with OS X. I actually almost bought one back then, but we couldn't get credit from Apple, so I ended up not getting a Mac until 2004.
 
Yup, that's the one I bought.
I bought it to replace my performa 5200. As a matter of fact I was preparing for the introduction of the euro in 2002 so I wanted a new computer to test my converted filemaker pro files. I started to use him in januari. You can imagine how pissed I was when apple introduced the iMac G4 in februari. The machine I bought to start using was very obsolete in a couple of months.
 
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