On 3/27/17 7:37 AM, Systems Glitch via cctalk wrote: >> I don't know of MOS memory appearing in 11/20s as built by DEC, but there's >> no reason against it.
There were 3rd party cards, Monolithic Systems, for example. The problem with the 11/20 is that hex wide cards don't fit, the fans overlap the unibus jumper area. If you ever see hex-wide cards with a big notch in one end, they were designed to work in the 11/15 11/20