NetBSD/sun3 runs on these sun3 and sun3x architecture machines:

Model MHz RAM RAM Expansion Bus Slots Type
Sun 3/50 15.7 4 3rd party n/a n/a sun3
Sun 3/60 20 24 24 30-pin SIMM: 1x9 100ns P4 (video) 1 sun3
Sun 3/75 16.67 16 VME bus memory cards VME bus 2 sun3
Sun 3/80 20 40/64 16 30-pin SIMM: 1x9 or 4x9 100ns P4 (video) 1 sun3x
Sun 3/100 series 16.67 16 VME bus memory cards VME bus 3 sun3
Sun 3/200 series 25 64 VME bus memory cards VME bus 12 sun3
Sun 3/400 series 33 128 VME bus memory cards VME bus 12 sun3x
Sun 3/E 20 4(?) VME bus memory cards VME bus n/a(?) sun3

The RAM column is maximum supported RAM in megabytes.

Sun made a variety of VME bus cabinets with different numbers of bus slots; ultimate RAM and I/O expansion is more a matter of how many bus slots there, rather than the particular CPU you have.

The Sun3/80 RAM capacity varies with the boot ROM revision - 3.0.2 allows 40MB, 3.0.3 allows 64MB.

The Sun 3/50 has 4MB soldered on the motherboard; all RAM expansions for that workstation were provided by third-party solutions (read "hacks") of one kind or another.

The Sun 3/E is a 6U VME single-board computer intended as an embedded system component.

The Sun 3/80 workstation and Sun 3/400 series servers are sun3x architecture machines based on the Motorola 68030 CPU. They were Sun's last design using Motorola microprocessors, and were somewhat complicated by the fact that the mc68030 has an integrated MMU in the CPU chip.

Sun Microsystems stopped designing systems with Motorola microprocessors when their own SPARC CPU design became a commercial success.