+1
I just want to add that older Photoshop versions might be still interesting to use because they supported older plug-ins.
There used to be a whole market for third-party plug-ins.
I'm just speaking as a layman here, of course.
I *assume* it's a bit similar to the VBX plug-ins that were exclusive to 16-Bit Visual Basic (VB1 to VB3 or VB4 16-Bit).
Also good about the Mac Pro 4.1 or 5.1 is the 64-Bit EFI and the more recent processors.
The older 3.1 did have 64-Bit EFI but didn't have Intel-VT compatible processors, I believe, which is bad for VMs.
The older 1.1 and 2.1 model has Intel-VT but has a 32-Bit EFI.
This means that the 32-Bit kernal of OS X is being loaded. Not relevant for applications per se, but for all the kernal stuff. Including KEXTs!
So a VM software like VirtualBox is being limited to ~4GB. For all VMs running same time, not just one VM.
Parallels Desktop 10 for Mac als needs 64-Bit EFI host.
Mac OS 9.2.2 is still being patched by the Mac community, I think.
It tries to make it run on non-supported G4 models.
Things look good so far, but not all features are working properly yet.
PS: There are of course als Tiger (10.4) fans out there.
Essentially, Tiger is to PPC users what Snow Leopard is to x86 Mac users.
They may still have an interest in 64-Bit G5 systems or running Classic Environment.
People into networking might still have an interest in native hardware for Jaguar (10.2) or Panther (10.3).
They support a large variety of networking protocols and thus can bridge old classic systems and new OS X systems.
I vaguely remember that performance of Classic Environment on Jaguar or Panther used to be better than it is in Tiger, too.
Screen drawing was smoother, I believe.
Edit: That brings back memories! I used to be a late Cheetah user (10.0) when I got an iMac G3. ^^
It was in the 2000s, when I learned to upgrade that Mac from 8.5 to Cheetah.
I fondly remember using it to watch Pokémon on the internet (RTL2 website?), thanks to Flash Player.
At the time, the latest plug-in still had worked with the old Internet Explorer 5.x.
Interestingly, Cheetah wasn't that bad, also.
After I've added to RAM (from 32MB to 96MB?) it ran acceptable. Not exactly smooth, but okay.
I've later upgraded to Puma, to get some more recent software running.
It was a really fine piece of software, too.
Then I went further, over to Jaguar.
But by that point somehow I occasionally had missed the old Cheetah GUI a bit.
The introduction of brushed metal surfaces wasn't so pretty, it didn't fit the iMac G3 style.
"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel
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