On 5/18/18 11:00 AM, Alan Perry via cctalk wrote:
On the back, the bottom, wider slot was open, the two
slots above occupied, and the upper two had blanking plates.
the empty slot is where the CPU goes.
the upper two are 'DIO' slots
more than you ever wanted to know is at
http://bitsavers.org/pdf/hp/9000_300
the most common 300 series that show up are the 310/320