CDC Cyber205 supercomputer


The Cyber205 was a CDC (Control Data Corporation) designed "supercomputer".
From 1983 to 1991 one was installed at SARA (Academic Research Center)
to serve the universities and the Center of Mathematics in Amsterdam.
The CY205 was my last project as a CDC engineer.

The Cyber205 was a so called "vector" machine.
Additional to the conventional scalar processor it possessed two vector pipelines,
which each produced a 64-bit floating point result per clock cycle.
This clock cycle was 50MHz, slow compared to current clock speeds.
Reason for this were the large distances between logic components.
The Cy205 was a 0.1Gigaflop machine.
The memory was constructed of many parallel operating "banks".
The data busses had a width of 512 bits allowing 8 floating point numbers being red or written simultaniously.
Input/output was made by external communications- and front-end processors accessing memory directly.
The power bill for this machine was 25.000 guilders ($15000) per week.

Below I show some pictures that were taken during installation during end 1983.



This picture was used by many newspapers.
To satisfy the photographer I had to maintain this posture for a long time.
I do not fullfill a meaningful task here.



The backside.
The memory and attached perpendicalar the scalar processor.
After that at left the vector pipelines.
The cabinets were about 7 feet high.
At installation the memory size was 1 million 64 bit words. (8Mbyte).




Equipment was installed on a raised floor. Below were connection and power cables.



Pipes with cooling water.
Not the CY205 but a CY990 front end processor.
The CY205 had a freon cooling system.



Room with disk memory.
Capacity was 100 or 200Mbyte per cabinet, model dependent.



Part of the vector pipelines.
The horizontally places printed circuit boards contain memory with microcode.



The installation crew.
Technicians for the mainframe, communications processors and cooling.





Part of a logic panel with chips.
Clips applied pressure to a chip seating it on a copper pipe with freon cooling.
The rows of small dots are contacts to attach a scope probe for troubleshooting purposes.




Front end processor consoles.

Goodbye after some years of good service (CY990 mainframe).










My thanks to Walter Lioen (SARA) for dates and numbers that slipped my mind and also for the
picture at the top of this page.