Control Data Corporation (CDC) had a strong history of creating powerful mainframe computers, with an emphasis on the scientific computing customer base. One of the most famous computer architects to emerge from CDC was Seymour Cray. While he went on to form his own company, work continued at CDC in developing high-end mainframe computers (aka supercomputer) — led by another famous architect, Neil Lincoln. As Cray competed against CDC, it became apparent to top management that it needed to decrease the development time for the next generation computer — thus a new approach was considered for the follow-on to the CDC Cyber 205.
After being spun off from CDC in September, 1983, ETA had the goal of producing a supercomputer with a cycle time under 10ns. To accomplish this goal, several innovations were made by ETA. Among these are the use of liquid nitrogen for cooling the CMOS circuits of the computer.
The ETA10 successfully met the company's initial goals (10 GFLOPS), with some models achieving a cycle time of about 7ns, which was considered rapid by the standard of the mid-1980s. The planned 1987 follow-on was supposed to be designated CYBER-250 or ETA-30, as in 30 GFLOPS. ETA was eventually reincorporated back into CDC, and ETA ceased operations April 17, 1989.
The ETA10 series could run either ETA's EOS operating system, which was widely criticized for various problems, or a port by Lachman Associates, a software personnel firm, of UNIX System V (Release 3). While EOS suffered a reputation for poor quality, ETA's UNIX was better received by customers.
Use of the ETA10 was rather complicated, and required all programs be loaded via attached Apollo Computer workstations. The program would then run once, and to run again would require re-loading from the Apollo. The ETA10 itself had no graphical console or local network interface, and all visualization of resulting data was performed by separate workstations after being retrieved from the Apollos. Programming for the ETA10 series could be done in FORTRAN, C, or CDC Cyber 205 assembly language.
It is a mistake to believe that ETA's demise was based solely on operating system choice or existence. The Fortran compiler (ftn200) had not changed from the CDC205. This compiler retained vendor-specific programming performance features (known as the Q8* subroutine calls) in an era when supercomputer users were realizing the necessity of source code portability between architectures. Additionally, the compiler optimizations were not keeping up existing technology as shown by the Japanese supercomputer vendors as well as the newer minisupercomputer makers and competition at Cray Research.
In general, computer hardware manufacturers prior and up to that period tended to be weak on software. Libraries and available commercial and non-commercial (soon to be called open-source) applications help an installed base of machine. CDC was relatively weak in this area - it is worth noting that some of the best operating systems that CDC provided to customers was a productized version of an OS written by Lawrence Livermore Laboratories.
The ETA10F and ETA10-G (7 ns clock cycle) were the highest-performing members of the ETA10 line, and used liquid nitrogen cooling to achieve rapid cycle times.
Less-costly air-cooled versions were later offered, such as the two-processor ETA10-Q (19 ns clock cycle), and the ETA10-P, which was also called "Piper".
Any of the ETA10 models could be built in either single- or multi-processor configurations.
Between the highest-performing, liquid-nitrogen cooled models (ETA10-E, G, etc.) and the cheaper, air-cooled models (ETA10-P, Q, etc.), the ETA10 line spanned a 27:1 performance range. Peak performance on the top-of-the-line models reached 10 GFLOPS.
The ETA10 line adopted novel approaches to physical construction, as well as innovative computer organization and lay-out processes:
The benefit of using CMOS lies partly in its rapid switching speeds, in the low tens of picoseconds; the ETA10 line put this to use with an approximately 100 MHz clock speed. Further, although slower than ECL at the time, CMOS circuitry could be laid out on a wafer more densely than permitted by ECL, thus ameliorating various off-chip and on-chip delays. These delays were managed through careful tuning of each PCB manufactured in conjunction with the logic technology - incorporating two key technologies that became known as JTAG and BIST. The IC's used for the ETA product were 20K Gate Arrays fabricated using 1.25 micrometre technology that were accessible from the VHSIC program at Honeywell - mainstream commercial technology was at the 3 to 5 micrometre technology at that timeframe.
The IC's were designed using a combination of internally developed tools (simulators and placement), while using some of the first commercial EDA tools from a vendor called Mentor Graphics for schematic capture. Prior to the use of schematic capture at ETA, the designers had used textual netlists to describe the interconnection of the logic circuits.
Noteworthy is that ETA had to invent methods for creation of 44 layer PCB's, as there were no external vendors supplying such advanced technology at that time.
It is of particular note that in order for this type of cooling to be effective, a closed loop system was required. ETA had to innovate to make this possible, since there were not any commercially available solutions in the market.
Before ETA Systems was reincorporated into CDC, a total of 25 systems were delivered. Among the recipients were: