What Happened to Prime Computer
The computer industry is an extremely unstable business where a slight
technical or marketing advantage can leverage a small company to stardom
overnight. And once that advantage is gone, a company can fall just
as rapidly. Thus, such one time powers as Univac, General Electric, and
Control Data Corporation are out of computing (or out of business).
And other former powers such as Cray, Data General, Digital Equipment,
and Apple have lost considerable influence. In this environment, the
demise of Prime Computer wasn't shocking. Still it is
sad, because Prime Computer and it's sister company, Apollo Computer,
had excellent operating systems which fit many users needs better
than Unix or any OS from MicroSoft. Today, both companies and their operating
systems are gone. Why?
A Short History
In the late 1960s there was a very innovative operating system project
called Multics at GE, Bell Labs, and MIT. Many well known people worked
on this project, which developed many techniques used in modern
operating systems. In particular, Ken Thompson and Dennis Ritchie from
Bell Labs worked on Multics, and they used this experience in designing
Unix. In fact, the name "Unix" may have been chosen because it's
authors considered it to be a "castrated version of Multics".
William Poduska and other software engineers worked on the Multics
project at MIT. In the early 1970s he and several others left MIT
to form Prime Computer Corporation. They also used Multics as the
foundation of their operating system, which they called Primos.
Prime computers were unique in certain ways. This was long before the
advent of PCs and Unix workstations. Computing had been totally dominated
by mainframes made by IBM, Control Data, and others. However, DEC and
Data General had captured a share of the computer market with their
16 bit minicomputers. Prime entered this market with a 32 bit minicomputer
aimed at scientific users. These Prime computers were affordable,
easy to use and administrate, and fast. Moreover, the 32 bit architecture
supported large address spaces needed for scientific computation. This
was especially true after Prime implemented virtual memory which they
did very early.
Indeed, Prime implemented:
- Primos which was a somewhat Unix like OS.
It wasn't as powerful as Unix, but it was more consistant and very
friendly. It was orginally written in Fortran, altho Prime
eventually changed to a combination of Fortran, plp, and spl. It
had excellent online help which was rare in operating systems at
that time. In time Prime added an excellent scripting language
called CPL, and a very powerful and friendly user validation and
- 32 bit architecture
Prime developed the first 32 bit CPU for a minicomputer. This
CPU also included an excellent floating point processor which
made Prime computers superb for scientific computations. (Other
minicomputers such as DEC's PDP 11 series used 16 bit CPUs and
often did floating point computations via software rather than
using hardware.) Prime was also the first computer company to
add virtual memory support to their OS. At some point they also
added hardware to support quad precission arithmetic which added
even more to its abilities to do scientific computation.
- Primenet support.
Prime was one of the first companies to recognize the importance of
networking. They developed a proprietary networking system called
Primenet which was similar to a combination of telnet, rpc, and nfs.
So why did Prime fail?
People's opinions vary on this. Here is my opinion.
Prime grew from a startup into a Fortune 500 company overnight.
To do this Prime brought in high level executives to guide the
company. These executives made changes. In the short run these
changes lead to better products and faster growth, but in the
long run these changes also lead to Prime's demise.
The changes included:
- Poduska and his crew wanted to build computers for scientists.
They designed the Prime for this and they soon felt the need to
integrate graphics displays into the computer to form a scientific
workstation. Meanwhile, Prime's business executives wanted to
make bigger and bigger machines to sell to the business market.
As a result, Poduska and his crew left Prime to form Apollo
Computers which built scientific workstations based on a very
Primos like operating system called Aegis.
| Apollo Computer
Apollo Computer went on to become a major computer company.
They really defined scientific workstations and dominated
the market until Sun came along. After this Apollo was
purchased by HP who changed the OS from Aegis to HPUX.
Poduska and his crew started another company. Unfortunately,
I don't know it's name.
|| Prime Computer
Meanwhile, Prime continued to innovate but at a slower rate
than before. Prime continued to attract scientific users, especially
for CAD and GIS. But they became less and less competitive in this
market. On the other hand, Prime became more and more of a
business computer. In particular, Prime ran a Pick system
called Prime Information which made it very popular in the
pre SQL data base market.
- In the early days, Prime had serious quality control problems. Prime
addressed these problems very successfully, and by 1981 they were
producing very reliable computers supported by a world wide network
of Prime field engineers. They also had customer training centers
around the world which offered excellent training.
The down side of all of this was the fact that Prime hardware was expensive,
and Prime support was expensive, and Prime training was expensive;
and Prime did everything possible to keep other companies from
selling Prime compatiable hardware, third party support, and
training. Thus, independent hardware and support vendors encouraged
potential customers to use other vendors systems. This hurt Prime
and helped it's competitors.
- Indeed, Prime and Apollo were too proprietary for their own good.
AT&T couldn't make computers because of government anti-trust
regulations, so they gave universities access to Unix source code.
This allowed students and researchers from all over the world to
enhance Unix and make it into the powerful OS it is today. AT&T
then made some money from Unix by licensing it to computer
manufacturers to put on their hardware. Prime and Apollo should
have done something like this with their operating systems. They
could have made a good profit from such an endeavor since they weren't
hampered by government anti-trust regulations.
- Prime finally went on a buying binge where they were going to
grow by buying successful companies. (Apparently, they had little
faith in their own R&D department.) They bought CAD companies
and GIS companies and so on; but most of them didn't do well
after joining Prime. Finally, Prime purchased Computer Vision.
This was a huge purchase for Prime which required all of Prime's
capital to pull off. This made Prime venerable to hostile
take over. A small company (whose name I forget) supported by
lots of high risk, high interest junk bonds attempted such a take over.
Prime found a white knight who successfully fought off the hostile take
over by purchasing the company with their own high risk, high interest
junk bonds. This battle took about two years during which time
Prime conserved money by slashing R&D, Sales, etc. After the
battle Prime tryed to pay it's huge interest bills by cutting
still further. Prime's major products soon became outdated overpriced
minicomputers in a market dominated by multi vendor client server
In the end, Prime went bankrupt. They tryed to save individual
divisions by spinning them off as separate companies. In some cases
this worked. In other cases it didn't. Computervision still
exists and may be doing ok. Prime hardware manufacturing died and
took the Primos operating system with it. I don't know what happened
to VersaCad or Prime's GIS software.
Links to the remains of Prime Computer
- Computervision Corporation Home Page
Computervision is what is left after the Prime/Computervision
merger and subsequent bankrupcy. This Web page describes
Computervision's products. Although most of Prime's technology is
gone, Prime veterans will recognize a few of the CAD offerings.
This link may be dead - along with the company I suppose. At
least, I couldn't find any trace of this web site or the
company when I updated this page in March 2002.
- First Solutions
At one time, First Solutions Inc. was a fairly small third party
vendor in the Prime market. To the best of my knowledge, they
are the only company left who still handles Primos based computer
- Malcolm Hoar
At one time, Malcolm Hoar was a Prime District Support Manager.
His web site contains a couple interesting pages on Prime Computers.
These are at (1)
Multics was a landmark in operating systems created by MIT's Project
MAC, Bell Telephone Laboratories, and General Electric Company's
Large Computer Products Division in the 1960s. It introduced
many new concepts in OSs, and veterans of the Multics project
went on to use these concepts in creating Unix, Primos, Apollo Domain,
and other OSs. This Web page is a real tribute to the people
involved in Multics.
- Multics General Information
This is one of the first Multics related web sites. I
originally wrote the description for Multicians.org for this
site. The description applies equally well to both sites.
They are both great web sites.
For more information email
© 1996 David Mandel All rights reserved.
Created 6/96 by D. Mandel
Last updated 8/96 by D. Mandel