---
title: OSM Computer Corporation Zeus 3X
categories:
- Computers
types:
- Professional Computer
origins:
- U.S.A.
years:
- '1983'
cpus:
- Zilog Z80A
params:
  name: Zeus 3X
  image: /media/museum/photos/osm_zeus-3x_1.jpg
  company: /companies/osm-computer-corporation
  company_name: OSM Computer Corporation
  specs:
  - label: NAME
    value: Zeus 3X
  - label: MANUFACTURER
    value: OSM Computer Corporation
  - label: TYPE
    value: Professional Computer
  - label: ORIGIN
    value: U.S.A.
  - label: YEAR
    value: '1983'
  - label: CPU
    value: Zilog Z80A
  - label: SPEED
    value: 4 MHz
  - label: RAM
    value: 64 Kb + 64 Kb x number of users (up to 32) = 2.1 Mb max.
  - label: TEXT MODES
    value: 80 x 25 CP/M standard
  - label: GRAPHIC MODES
    value: none
  - label: COLORS
    value: monochrome through terminal display
  - label: SOUND
    value: None
  - label: SIZE / WEIGHT
    value: 10x19x27 inches / 60 lbs
  - label: I/O PORTS
    value: 4 x serial ports (2 users, 2 master), 1 x parallel port, 1 x 3270 synchronous port
  - label: BUILT IN MEDIA
    value: Hard disk (from 12 to 140 Mb) + 20 Mb tape cartridge storage
  - label: OS
    value: CP/M, M/PM, MUSE or ZMOS
  - label: POWER SUPPLY
    value: Built-in PSU
  - label: PRICE
    value: 'USA (1983) : $10,800 (4 users systems) / $2,294 (4 users increment)'
  oc_id: 1336
  source:
    url: https://web.archive.org/web/20230202150823/http://www.old-computers.com/museum/computer.asp?c=1336
    date: '2023-02-02'
---

OSM Computer Corporation, based in Santa Clara California, produced several multi-user CP/M computers called Zeus.

The Zeus 3X was released in 1983, and is a natural follow-up of previous systems: [Zeus, Zeus II, Zeus 3. The Zeus 3X was available as the same time as the](/museum/osm-computer-corporation-zeus/)[Zeus 4](/museum/osm-computer-corporation-zeus-3x/), in which it differs in some features (more users, more memory, tape drive, real time clock, etc.) making it more suited for larger companies.

The OSM Zeus 3X is a Z80 based multi-user computer that supports a single hard drive (from 12 to 140 Mb) and up to 32 users (8 only for the Zeus 4) via dumb terminals plugged into RS232 ports. The ports supports several terminal emulations as well as serial printers and modems.

The Zeus computer uses MUSE (Multi User System Executive) as its operating system, a CP/M compatible OS for multi-user computers from OSM. It incorporates all the standard features of CP/M, while adding file management capabilities such as multi-user file sharing, password protection, print spooling, data security and auto-searching. Later, the ZMOS operating system, another multi-user CP/M compatible OS, was also available.

In the november 1984's issue of Computerworld, there is an article describing how Pepsi bought and used Zeus 3X computers to help them cope with orders processing through these multi-user file sharing systems.

<table> <tr> <td></td> <td>We need more info about this computer ! If you designed, used, or have more info about this system, please send us pictures or anything you might find useful.</td> <td></td> </tr> </table>