Altos 186 and 486 systems did indeed run the Intel 80186 processor, which were passed over by the PC world.

Typically there would be one to four terminals attached, one of which was the system console. The version of unix that it ran was a port of Xenix, which was Microsoft''s port of Unix. Yes it was "real" unix, albeit a somewhat limited one. However, most unix software could be made to run on it.

Altos computers of this era were Intel based but most of them were not "IBM compatible." Altos did not see any need to do that since their machines were never intended to run MS-DOS.

I worked at Altos when the 186 system came out. I porterd a version of the Pick OS to it in 1984 (a solo effort, which was never offered for sale). And I can tell you why it was a slow pig running zenix - the size was made small by removing hardware to a bare minimum, and in the balance the main cpu had to also be the CRT controller - the OS had to sit 2nd seat to the controller, or you wouldn''t see anything.
I have one of the prototypes, and it still works.

I attempted to use the 80186 based Altos many times, but it was a failure from the beginning. It was officially called ACS486.

It''s speed was horrible, and the reliability almost nonexistant. It was a blunder of gigantic proportions.

I bought several at the ''bargain'' price of $4k each, and soon discovered why the great discount - they were junk.

Howver, the other Altoses I''ve used, including ACS8000-10, ACS580, ACS586, ACS2086, ACS1000, and ACS2000, are easily among the best systems in their class.

My OS of choice from the beginning was Oasis8-16/Theos, and it still would be if the Altos was still available.

Altoses running Theos were unbeatable - Xenix/Unix were slow and made for support groups - not efficiency and productivity, where it counts.