jon(a)techniche.com (Jon Healey) wrote: It reads to me like what you got was the *processor*. And I have to wonder, why did you take it out? OK, I understand for transport but you also wrote that there was an expansion card frame (which might have more I/O cards) and other units in the rack. They may not be essential to operation of the processor but they probably do go together. Processors ain't everything ya know. OK. If you take the top off, the cards in in the wider cage right behind the front panel are the CPU proper (in slots 1-7 I think, with options in 8 and 9 and maybe 10, though I may be off by one or two here -- it's been a while since I looked) and the I/O interfaces. The cards in the narrower cage about halfway back are memory (core) and drivers for same. The not-card-cage areas contain power supply and fans. There should be part numbers and legends on at least some of the card ears that give some clues what the cards are/do. Also the cards themselves will often have part numbers etched. Of course I don't have my books handy so can't post a handy decoder chart just now (and doubt it would be complete even if I did). Feel free to post a list, then sit back and watch us guess what you've got. Given that this one says "Microprogrammable" on the front panel I wonder if it has the WCS (Writable Control Store) option. All that said...the 2100 is a second-generation HP mini from 1972, the follow-on to the 2116/2115/2114 and predecessor to the 21MX that came later in the 1970s. These processors formed the basis of the HP2000 time-shared BASIC and HP1000 real-time computer lines, as well as many other special-purpose computer systems that HP developed and sold. Overall they are a 16-bit two-accumulator architecture; the 2100 is part hard-wired part microcoded with room for growth in the microcode, while the earlier 2116/2115/2114 were purely hard-wired processors. I'm interested but am thinking that you're in New Hampshire and I'm in California. Shipping is possible but you're right, you can't just toss this in a cardboard box with some peanuts or bubblewrap, so if someone closer by says the magic words ("I'll come pick it up") or you decide you want to keep it I'd say go for it. Besides, I'd want you to go back for the rest of it. Foo, I want you to go back for the rest of it *anyway*. -Frank McConnell