Olivetti made PCs for AT&T. So for example the AT&T 6300 is an Olivetti M24 with different colors and branding:

6300 -> M24
6300 Plus -> M24 with 286-6 mainboard -- not to be confused with the M24SP as that is an M24 with a 10MHz crystal
6300 WGS -> M240
6310 -> M28
6312 -> M28 12MHz?
6312 WGS -> M280
6386sx/el20 -> M300-xx ?
6386sx/el -> M300-xx ?
6386/25 -> M380-25 ?
6386/33 -> M380-33 ?
6386E WGS -> M380XP9 ?

Can you help me to understand better?
Last edited by 1ST1; December 2, 2021, 01:48 PM.