3620 top view
3620 card cage showing base L-bus cards required to run Genera
([PROCESSOR] and [NBS FEP I/O]). The 3620 has no spare L-bus slots so cannot
support color.
Of the 6 S-bus slots, two have to be occupied by the video and disk interface
cards, the remaining slots can accommodate memory cards (in this case 4 x 1MW).
The 3620 is the minimum Symbolics system, other systems have more card slots
(L-bus and S-bus) (e.g. see 3650 card cage).