It was too long ago for me to remember precisely which system it came with, but I’m almost certain my printed copy of the operating system source code was for Digital Equipment Corp.'s (DEC) Rainbow 100 CP/M-86/80. It filled two thick 3-ring binders.
There was (somehow) no extra price paid to get that. But then again, it was bought directly from DEC under a special discount program for employees of their industrial distributors.
