---
title: NEC APC III
categories:
- Computers
types:
- Professional Computer
origins:
- Japan
years:
- '1983'
cpus:
- Intel 8086
params:
  name: APC III
  image: /media/museum/photos/nec_apciii_system_s1.jpg
  company: /companies/nec
  company_name: NEC
  specs:
  - label: NAME
    value: APC III
  - label: MANUFACTURER
    value: NEC
  - label: TYPE
    value: Professional Computer
  - label: ORIGIN
    value: Japan
  - label: YEAR
    value: '1983'
  - label: END OF PRODUCTION
    value: Unknown
  - label: BUILT IN LANGUAGE
    value: None
  - label: KEYBOARD
    value: 101-key with 12 function keys, cursor and numeric keypads
  - label: CPU
    value: Intel 8086
  - label: SPEED
    value: 8 MHz
  - label: RAM
    value: 128 KB up to 640 KB
  - label: VRAM
    value: Unknown
  - label: ROM
    value: Unknown
  - label: TEXT MODES
    value: 40 or 80 columns x 25 lines
  - label: GRAPHIC MODES
    value: 640 x 400 dots bit-mapped color
  - label: SOUND
    value: Internal speaker
  - label: I/O PORTS
    value: Floppy Disk Drive, RS-232C, Printer, C-bus slot x 6
  - label: BUILT IN MEDIA
    value: 2 internal TEAC FD-55B-01-U 5.25'' floppy drives - 720 KB in native mode, 360 KB with the SLE board
  - label: OS
    value: Special version of MS-DOS 2.11
  - label: POWER SUPPLY
    value: Built-in power supply unit
  - label: PERIPHERALS
    value: External hard disk drives
  - label: PRICE
    value: About $3,000 with internal 10 MB hard drive 1984
  tabs:
  - photos
  forum_thread: 970
  photos:
  - title: LARGER VIEW
    subtitle: ''
    text: ''
    image: /media/museum/photos/nec_apciii_system_s2.jpg
  - title: FRONT PANEL
    subtitle: ''
    text: |-
      10 MD HDD version.

      Thanks to **Chevy**
    image: /media/museum/photos/nec_apciii_frontview_s1.jpg
  - title: REAR SIDE
    subtitle: ''
    text: |-
      **(1)** Keyboard connector\
      **(2)** Monochrome monitor plug\
      **(3)** External HDD controller card housing\
      **(4)** Colour RGB monitor DB9 plug\
      **(5)** Configuration switches\
      **(6)** Serial RS-232 interface connector\
      **(7)** Two additional serial ports\
      **(8)** Parallel printer connector
    image: /media/museum/photos/nec_apciii_rearside_s1.jpg
  - title: EXPANSION CARD SLOTS
    subtitle: ''
    text: |-
      An extra memory card is inserted in one of the four expansion slots.

      Thanks to **Chevy**
    image: /media/museum/photos/nec_apciii_expcard_s1.jpg
  - title: KEYBOARD
    subtitle: ''
    text: Thanks to **Chevy**
    image: /media/museum/photos/nec_apciii_keyboard_s1.jpg
  - title: INSIDE
    subtitle: ''
    text: Thanks to **Chevy**
    image: /media/museum/photos/nec_apciii_inside_s2.jpg
  oc_id: 996
  source:
    url: https://web.archive.org/web/20230324112835/http://www.old-computers.com/museum/computer.asp?c=996
    date: '2023-03-24'
---

The Nec APC III appears to be the U.S. version of the [NEC PC-9801](/museum/nec-pc-9801-f/), which was made in a variety of configurations.

This machine was partially IBM PC compatible, but neither the PC bus or BIOS were cloned. It had an NEC 7220 graphics chip which was not directly CGA compatible, but was much higher resolution, and quite fast for its day.

The CPU is an 8086 running at 8 MHz with 128K of memory. The system used an OEM version of MS-DOS 2.11, modified to work with its non-standard BIOS and hardware. Simple DOS applications that did not make use of IBM BIOS calls or of lower-level hardware would work.

Optionally there was an expansion board called **SLE** (for Software Library Expander) which some nicknamed *the SLEeze board*. This board included a second 8086 processor, Phoenix BIOS and memory. In conjunction with its accompanying software this board allowed for "more PC compatibility" by emulating a true PC clone with CGA graphics. Accounts of how well this actually worked vary.

NEC also ported a version of **System III UNIX** and released it as **PC-UX** available as an optional OS. NEC also provided a hardware-based virtual memory paging board for PC-UX which helped performance.

Other options included a 10MB hard drive. Memory was expandable to 640K.

Thanks to **Richard Bramante** for information and pictures.

<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>