G'day Paul -
Indeed, Ampex sold Nova-compatible computers from around 1977.
Ampex also sold memory systems for certain Nova series, PDP11, 11/70,
DECsystem 10 and DECsystem 20, IBM, Unicac and Sigma 7 and 9(!).  These
in addition to the disk drives, tape drives, controllers, fixed-head
disk emulators (using core) and OEM memory components.
Bruce Ray
Wild Hare Computer Systems, Inc.
Denver, Colorado USA
bkr(a)WildHareComputers.com
...preserving the Data General legacy: 
www.NovasAreForever.org
On 12/5/2023 4:07 AM, Paul Birkel via cctalk wrote:
  Although I knew that Ampex was a supplier of Multibus
non-volatile RAM
 boards (MC-8080 and MCM-8086) - Memory Products Division - I didn't realize
 that they had competed for a while in the DG-compatible market alongside
 companies like Digidyne, Fairchild, Bytronix, and SCI Systems (according to
 court documents and the trade press).
 Can anyone shed light on what they offered and when?  And perhaps why?
 Thank you,
 paul