I just verified that M8637-Ex cards works fine in both 11/83 and 11/84 systems. The same goes for M8637-Dx cards. I don't think I have any M8637-Bx or -Cx cards, so I can't try that. So to make it clear: MSV11-JD and MSV11-JE works fine in both Q-bus and Unibus systems. Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at softjar.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol