On Dec 12 2005, 21:17, Allison wrote: using uses Yes, you did say 73B. As I'm sure you know, there were two 73s, one dual M8192 and one quad M8190. The dual is QBus only, naturally, no PMI. The 83 is also quad, and is the same M8190 card as the 73, but with a faster clock (the earliest J11s won't run reliably at 18MHz let alone any faster) and slightly different bootstrap ROMs. 73 was sold as a 15MHz non-PMI system and the 83 as 18MHz PMI, but in fact you can move the 73 card below the memory instead of above it and it will work (if the memory is PMI, anyway!). In fact the OSs distinguish 11/73 systems from 11/83 systems simply by checking if they're using PMI. -- Pete Peter Turnbull Network Manager University of York