Yes, that's the one.
So, what is the difference between CPU Software 5.8 and 5.9?
Much like you pointed out, I also would not be surprised that 5.9 and, specifically, Z-5.8 (which is the only "5.8" I know of) are identical, besides version-related strings:
On the left is the legendary ROM as we know it, which I pulled straight from the MDD 2003 disc as you discovered, which I indeed confirmed to be 100% identical to the one which the "Mac OS 9 Lives! Universal" disc installs.
On the right is the only "5.8" ROM I know of, which I obtained from your ROM archive on GitHub, @joevt, which is credited as "2003-04-03 - Mac OS ROM (New World 10.2.1) Mac OS 9.2.2 Retail International CD", which checks out, as the "Z-" prefix is an Apple-chosen prefix for "International" English (as opposed to US English or UK English etc.).
The two have identical Created and Modified dates, down to the exact time. The Z-5.8 one is bigger in file size by exactly mere 4 bytes, and is probably because the literal string "Z-5.8" is bigger than and thus takes that little bit more of data to store than just "5.9".
I like it better that we stuck with 5.9, though, simply because it makes it clear, by being a higher number, that it is the latest version we can get, so it's clear to any user, and also because of the absence of any region-specific verbiage such as "Z-", which can be either confusing and/or distracting.
That being said, it is probably only cosmetic, and, if so, it wouldn't matter which of these two is used (not sure about any other "different" 5.8s out there, some of which might be older, if they exist). But since it was better to pick just one anyway, well, I'm glad we took the one that made the most sense.
On a little side note, though, perhaps it might be worth pointing out that, despite seemingly identical files (in size, and both resource and data forks), the System Folder that boots our MO9L "Universal" disc is 4 hours behind the same ROM contained in the image that gets restored into the volume we install it to (11:00 AM vs. 3:00 PM). I also find it curious that, when you checked the MDD disc, its ROM reported to you "8:00 PM". Those small hourly differences might be related to the regions / zones of our respective machines?
Anyway, thanks again to @DieHard and @MacTron for the original effort of putting together all the best parts of Mac OS into one place! And thank you again for all the help, @joevt. This finally puts this investigation to rest.
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Topic: Where did Mac OS ROM 10.2.1 CPU Software 5.9 come from? (Read 1152 times)
