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A > ATT > PC 6300   

PC 6300

The PC 6300 was in fact an Olivetti M24 sold under the ATT brand.

Launched a few months after the presentation of six new UNIX super-micro and mini ATT computers (march 1984), the PC 6300 was the first ATT system to be IBM PC compatible. It represented the low-end system of the ATT products.

But the PC-6300 (and the Olivetti M24) was an excellent PC compatible system, twice faster than the IBM PC XT computer thanks to a real 16 bit CPU, the Intel 8086, which ran at 8Mhz as opposed to the 8088 of the IBM PC running at 4,7Mhz. The standard graphic possibilities were also better than those of the IBM PC.

Michael Hildenbrand reports :
When I got it, there was also an option to get a 720k 3.5 floppy with it instead of the 5.25 floppy. When I got mine in 1986, one of the 5.25 floppy drives went bad and I had them replace it under warranty. It would have cost me $500 to replace it if I had had to replace it. Cool machine, anyway. I used that machine for many years!

David Punia adds:
During the early 80's, it became apparent that PC's were becoming an important tool to engineers and to businesses. The University of Vermont, where I worked at the time, was an early adopter of what later became common practice, that of requiring incoming students in certain disciplines to purchase personal computers.

In those days, compatibility was a huge issue, i.e. there was very little, so sole-source vendors were often chosen to supply PC's. The AT&T PC6300 offered a significant performance advantage over the IBM PC and others. It's full 16-bit processor/bus interface, 8 MHz processor, high resolution graphics modes (proprietary to Olivetti/AT&T) and 8087 math coprocessor socket made it a good choice for CAD, circuit analysis, and other graphical and math-intensive applications. There were a couple of 16-bit expansion slots also, but the card configuration was proprietary, eventually supplanted by the PC/AT's form factor for expansion cards.

The design of the chassis was interesting; the motherboard was accessed by removing the bottom cover of the system unit, exposing the entire motherboard. A daughterboard in the upper section of the system unit carried hardware for the expansion slots, and housed the drives. I still have one of these boxed away in my basement, with a side-attached hard drive chassis that could carry a full-height 5.25" hard disk. Mine has a 72 MB Seagate, about 5 pounds and $650 at the time, that dims the lights while it spins up ;-). and makes a loud clunk when the mechanical brake kicks in during power down.

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I was a third-party computer field service technician 1987-2002. The customer I serviced used AT$T 6300''s with an SNA card on IBM mainframe system. These were used as remote job entry stations attached to Printronix P600XQ line printers at 20 sites in New York City. The first time I opened the system case I was surprised to see that 120V power for the monitor was supplied through the DB9 connector on the monochrome video card, so servicing this model could be a shocking experience for the uninitiated technician! I recall we had to install a date patch for the AT$T operating system software to make it Y2K compliant.

Monday 17th January 2022
Christopher Platt (USA)

I used work in a Computerland service department and we sold a lot of the 6300s. They were really good computers with one very major exception. Their soldered in CMOS barrel shaped battery would die about every 1 to 2 years. Attempting to unsolder and resolder another battery was forbidden by the service agreement because it often destroyed the motherboard by causing issues with the multi-layered solder foils. So the only "official" way to service these was to replace the mother board entirely. But often times the replaced motherboard sat on a shelf for many months before shipping and the two year battery would have already been somewhat depleted when we got them. The advertising said the batteries should last 7 years but 2 was more like it. It was one of my least liked news I had to give 6300 customers as a new motherboard replacement at that time was $1700, a used one they had repaired about $900 if you could get one. So essentially a dead $3 battery just outside the 1 year warranty would cost the customer $1700 and a wait several weeks just to fix one. Most people didn''t go for it and just bought another PC from us (or in anger from someone else). It was impossible to convince my Computerland management to stock $1700 boards so weeks to repair them. Computers like these usually sold for 2-3k back then and repairs were very costly and time consuming.

Sunday 5th September 2021
Don Gray (United States)

My father was a product manager for the PC6300 line for AT$T. He brought home one of the early machines (still in the Olivetti grey plastic). The first machine had two 5.25" floppy drives.

Tuesday 14th September 2010
John W. Ellenberger (Fort Collins, CO, USA)


NAME  PC 6300
TYPE  Professional Computer
YEAR  June 1984
BUILT IN LANGUAGE  GW-Basic delivered on disk
KEYBOARD  QWERTY full-stroke keyboard, function keys, separated numeric keypad
CPU  Intel 8086
CO-PROCESSOR  optional Intel 8087 arithmetic co-processor
RAM  128 kb or 256 kb, expandable to 640 kb
ROM  16 kb
TEXT MODES  40 x 25, 80 x 25
GRAPHIC MODES  640 x 400 - 640 x 200 - 320 x 200
SOUND  Beeper
SIZE / WEIGHT  38 (W) x 37 (D) x 16 (H) cm / 14 kg
I/O PORTS  RS232c, Centronics, mouse, keyboard, monitor, 7 expansion slots
BUILT IN MEDIA  5.25'' disk-drive (360k or 640k) and optional 10Mb hard-disk
OS  MS-DOS 2.11
optional : Concurrent CP/M 86, UCSD p-system, PCOS, XENIX
PRICE  Monochrome, 2xFDD $2745 - Color $3395 - Mono+10 MB HDD $3975

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