Check out "the Unix Heritage Society": http://minnie.tuhs.org/cgi-bin/utree.pl to see what was "released" to the world. My memory is that DEC only released a very early version of Ultrix. The last release of Ultrix was something like 4.6 (I'll have the check my notes, but I'm traveling) - and on PMAX and VAX. Over the course of time, Ultrix ran on: PDP-11 models with a MMU both with and without separated I/D space, most of not all of the Vaxen (except for the 9000 I believe), and MIPS 2K,3K,4K systems that Digital made. Historical note: the original Alpha HW was brought up running Ultrix, but that was never a product ;-) Later version of Ultrix will run best on PMAX's made with a MIPS 4400 - which was the last "new" processor that Ultrix supported. On Tue, Jun 11, 2013 at 9:45 AM, Joe Ferraro <jferraro at gmail.com> wrote: Admittedly, posting without quick research, apologies... Where does one come by Ultrix sources these days, is it hobbyist licensable (or "abandonware"), and what hardware is needed? Joe On Tue, Jun 11, 2013 at 9:31 AM, Sampsa Laine <sampsa at mac.com> wrote: I'm going for Ultrix for now - I'm a total TOPS-20 noob, would need a lot of hand-holding to get the thing to run I fear... sampsa <sampsa at mac.com> mobile +961 788 10537 On 11 Jun 2013, at 11:36, Robert Jarratt <robert.jarratt at ntlworld.com> wrote: