IBM 1501989 XM switches

[maelstrm]

Good evening, Federation!

On the 1501989 XM memory expansion card, what are switches 1-4 used for? I have a fully-populated expansion card (1501989XM) going into an IBM 5150 motherboard (also with full rows of memory).

Thanks!

 

[modem7]

1501989 XM

Online sources indicate that the card is an 'IBM 64/256KB Memory Expansion Option'.

See [here] for information on the card, which includes the switch settings.

 

[maelstrm]

Thanks modem7. Got it working with 512K.