Dos 6 and PC286
I have an xt bb. I added the Sota 386si, an 80386sx 16mhz accellerator.
Today, it's not cost effective if you can get a cheap 386bb, but a couple
years ago it really was. Its wierd in that I don't have any extended ram
but otherwise have a 386 system, though on an xt bus.
Ron