So, this post (which I loved) brings back a lot of memories for me (having joined Solaris Kernel Development in 1996, when ppc was still a thing -- if barely).
If I may, a quick anecdote: back in MPK17 (now Facebook!) my office was next to that of Mike Sullivan, who was one of the lead engineers on on297, our internal name for Solaris 2.6. As part of his nature of running latest bits on everything around him, Mike had in his office (among many other things) a laptop. Over my years of working in Menlo Park, I can remember exactly one theft: one night, that laptop of Mike's -- and the laptop alone -- was stolen. The funny thing (and the reason this story made me think of it): it was a ThinkPad 850, an IBM PReP laptop running an internal build of on297 (to my knowledge the only one that ever existed) -- and I have often wished I could be there when the thief tried to unload what was surely the world's most arcane laptop, if not its most useless...
I worked at Sun for a while and one thing I recall was how we could grab any abandoned hardware laying around and take it for whatever you wanted.
I recall wheeling an archaic 4ft tall tower format disk enclosure I found in a server room corner to my desk and connecting it to either the x86 dual CPU desktop I used (which had since lost all its side panels before I inherited it) or an ultra 30 I had there, I forget which.
I then set up the internal s10 build with ZFS and playing around with it. That's when I first become confident in the benefits of Solaris over anything else out there at the time. Used Solaris 10 as my main desktop for nearly 4 years
We even had intel itanium desktops for testing. Always referred to as the "itanics".
ppc is still a thing, my project computer is a power9. The only reason it isn't my daily driver is because I can't help but tinker with it. Being able to rewrite the supervisor chip code in order to get that fan curve just so, and having the support of unabridged and NDA free documentation - instead of grinding through reverse engineering... feels good. I highly recommend it, just stick to known working GPUs, the mmu actually does its job.
To be clear, you're talking about the original POWER ISA. The PowerPC ISA has subsequently been renamed the Power ISA (not to be confused with the POWER ISA). Confusingly, IBM's POWER CPUs (POWER3, POWER4, POWER5, POWER6, POWER7, POWER8, POWER9) since POWER3 implement the Power ISA (then known as the PowerPC ISA), not the POWER ISA. POWER2 was the last CPU to implement the POWER ISA.
PPC in 1996 was not "barely a thing". IBM could win over Apple, and later Sony for the "Cell" CPU on PS/3, and Motorola sold to automobile and other embedded apps in quantities. It's just that sometime around 2005-2010 or so the investment into new competitive fabs became so astronomically high that it just wasn't good business anymore for CPUs produced in quantities below x86 and ARM.
If I may, a quick anecdote: back in MPK17 (now Facebook!) my office was next to that of Mike Sullivan, who was one of the lead engineers on on297, our internal name for Solaris 2.6. As part of his nature of running latest bits on everything around him, Mike had in his office (among many other things) a laptop. Over my years of working in Menlo Park, I can remember exactly one theft: one night, that laptop of Mike's -- and the laptop alone -- was stolen. The funny thing (and the reason this story made me think of it): it was a ThinkPad 850, an IBM PReP laptop running an internal build of on297 (to my knowledge the only one that ever existed) -- and I have often wished I could be there when the thief tried to unload what was surely the world's most arcane laptop, if not its most useless...