The Jim Austin Computer Collection

IBM 3084

Cambridge University Computing Service

Phoenix 

This is a prime example of a large 1980's main frame. The IBM site (http://www-1.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3084.html) gives a list price of the machine of $8,700,000 in 1982 and shows the example of a system. The machine was IBM's most powerful computer in 1982.

The machine is water cooled so it comes with a chiller to take out the excess heat. It runs off 400Hz mains power and so needs special rotary converters to do this, these are also preserved. As an extra, the raised floor that went with the machine was also removed. The machine now sits on it in the buildings that store the machines.

The machine came from Cambridge University Computing Service where it was named Phoenix. The first part of the machine was installed in Cambridge in 1982 as 3081D then upgraded to the 3084 in 1989 (See http://www.cl.cam.ac.uk/UoCCL/misc/EDSAC99/history.html for a time line/history of the Computer lab where the machine lived). It ran until 1995, and was removed on 18 Sept 1995. It was the last mainframe to be used by the University. Unfortunately I was only able to get one half of the machine, in effect a 3082. The IBM site given above indicates that the machine will run each of the units individually. When we disconnected it there were only a few wires between the machines.

The machine was running before we removed it, but is not running now. The machine was taken out with great care and has all the manuals that also say how to put it together. Quite unusual for a machine of this size.

The machine in the collection is made up of:

A processor unit.

3082 Processor controller.

3081 Processor Unit.

3274 Tape Control Unit.

4670 Tape Drive Unit.

3087 Coolant Distribution Unit.

3089 Power distribution unit.

3278 Display console.

8880 Disk Drive Control Unit.

3287 Printer.

3278 Display console (x2) type 2A..

Chiller Unit.

Calcomp plotter that ran with the machine.

All cables to connect the machine together.

Full set of manuals.

Tools to remove the TCM arrays, racks for the manuals.

Unfortunately there were no disks supplied with the machine, although there was some boot software included.

The machine is a model K 3081 processor, containing 64K of fast buffer memory. It has 16 Megabytes of main memory. The 3082 Processor Controller undertakes initialisation of the 3081 processor.

The machine has a memory cycle time of 312 nanoseconds and is 8 bytes wide. It is compatible with other S/370 machines.

The machine used 3.4KVA and weighs about 9478 pounds.

A major feature of the machine was the Multi-Chip modules called Thermal Conduction Modules (TCM), shown here. They are helium filled units. 8 can be seen in the top of the main unit, with the pipes for water cooling of the modules. Each module consists of a Multi-Layer Ceramic substrate with up to 118 chips mounted. These are smaller versions of the ones used in the Fujitsu supercomputer in the collection.

The processor.

The processor controller (3082)

This connects to the System Console, the B indicates that this was the second of the two terminals used to control the two halves of the machine:

See http://website.lineone.net/~michael.s.grant/phx.html for some reminisces about the machine.