Don wrote:
I'd say it's not a problem to use MMX or even SSE1. It's really, really difficult to find a processor that doesn't support them. I've tried. I've really tried. I don't think many are still around: they all have motherboards which require really small hard disks that you can no longer buy. Certainly no-one is putting new software on them. Earlier this year I had to install Windows3.1 (!!!) on an ancient PC at work, to support an ancient but expensive bit of lab equipment. Even it was a Pentium II. Getting the spare parts for it was a nightmare*; we had to ship them from 600km away. Hard disks just don't last that long.
I do have a working Pentium around here somewhere. I even have a 486, though I haven't turned the machine on in 15 years. I no longer have a 386 (gave it away).
10 years ago, I heard that the 386 was commonly used in embedded systems. I don't know what the base level x86 used today is.
