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Comment by mburns | Hacker News Reader

MacOS System 7.5.x shipped on ~100MHz PowerPC chips with ~24MB of RAM, a bit higher in the later models. So the Watch most certainly has more processing power.

The real problem is emulating PPC -> ARM, which is a very slow process, and why the boot time is so long in the video.

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For the record, my Performa 6116CD which shipped with 7.5 had a 60 MHZ PPC 601 and 8 MB RAM. It could run on significantly less than that as well - in fact I believe it ran as far back as on some 80s machines.

Yup. I had an LC520 (25 MHz 030--not that far back from your 6116) that ran 7.5.x.

7.5.5 was the last version that ran on the Mac Plus, SE, Classic, and various other 8MHz 68000 Macs.

Right but it ran System 7.0.x.

System 7.5 had OpenDoc, so it ran in two modes: fast, light, and stable, OR with OpenDoc.

Not to mention the classic MacOS of that era had considerable amounts of code still written in 68k assembly, so a lot of what you're seeing is actually being emulated as 68k -> PPC -> ARM.

I think I saw "mini vmac" come up, so I believe this is emulating a 68000 directly, not with an extra layer in the middle.

It's emulating a Mac Plus.

Processing power is not only frequency and memory. Different instruction sets might show drastically different performance. Processor cache might be higher on old computer (or might not, of course). Memory bandwidth or latency might differ too. I remember reading comparison between 1990 mainframe and current intel server. Mainframe has much higher memory bandwidth and performed much faster on tasks where processor cache was insufficient.

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