the model 25 was many years later, and IIRC actually faster then the model 30. there was also a model 22 that was a full 360.
NO, DOS would not run on an 8k machine. the nucleus was 8k (maybe), then 10k, the 12k, I think even 16k after I had left. there was also BPS, load it in, then load in program (all from cards)\ Or there was BOS, not sure, but I think that was everything loaded on disk, but all run by commands from console then there was TOS in early days, like DOS but from a system tape. the fun job was the 1404 printer which I don't know if any museum have. it was wider, and the print head could be moved to the other side and it would feed and print on two tab cards at a time. On a 64k model 30, we ran BG and F1 at 24-26k each, doing batch work, F2 at 2k invoked by console commands (needed 8k(?) to run job control in a partition) for a spooling job, either reading cards to tape or print tape to printer. the tapes came from the remaining 7010 computer that did not have a printer on it. The two model 50s in the other room ran 7010 emulation but printed directly. we also had one 32k model 30, it could do one small job nearly ALL jobs were 360 programs that invoked 1401 emulation (we had ONE 1401 left) you could also use the console to run 1401 emulation without DOS (i think 2 options, one loaded in card deck, then allowed typing in config, otherwise just turn dials and store stuff into memory. we briefly had a 3rd party 2311 equivalent, which was cool because it had lights on the front to show (in binary) what cylinder the head was at. later, another matchine briefly had a 3rd party mod to extend memory to 96k (Ibm's limit was 64k), which failed so that upgraded to a model 40 as they had to have more memory for the application.
