I'm always somewhat amused when I run across one of these. In the early days Microsoft ported Windows NT to a LOT of different platforms, among them PowerPC. I actually have systems with two of the "alternate" processor types listed on the label, and I'd venture to guess the systems I have are the most common systems using these architectures. Even so, Windows NT won't run on any of them. Specifically, Windows NT won't run on PPC Macs(again, I'd guess by far and away the most PPC computers) since there is BIOS(at least as I understand it). I suppose that it would likely only run on the couple of(rare) PowerPC systems IBM made. In addition, NT 3.5.1 will run on certain MIPS processors. The major user of MIPS processors at the time was Silicon Graphics, but again NT won't run on an SGI system. I have no idea what MIPS based system it would run on. I'm mostly just throwing this up here for general interest-I think that both the fact that early versions of NT would run on PPC but not on Macs is well know, but it's always amusing to me when I see it.