ETA Systems was a supercomputer company spun-off from Control Data Corporation in the late 1970s in order to regain a footing in the supercomputer business, which CDC was being driven out of by an increasing legion of competitors. At the time CDC had become rather ossified, and Seymour Cray had left the company in the early 1970s, forming Cray Research and soon destroying CDC's sales. In order to regain some of the small-team flexibility that seemed essential to progress in the field, ETA was created.
ETA had only one product, the ETA-10 supercomputer. It was essentially a modernized version of the CDC Cyber 205 computer, and deliberately kept compatible with it. Like the Cyber series the ETA-10 did not use vector registers as in the Cray machines, but instead used pipelined memory operations to a high-bandwidth memory. The basic layout was a shared-memory multiprocessor with up to 8 CPUs (and up to 18 I/O processors), each capable of 4 double-precision or 8 single-precision operations per clock cycle.
Each CPU had up to 32MB of private memory, and the set of CPUs had common access to up to 2GB of shared memory. Most CPU load/store instructions could not touch the shared memory, however, and I/O operations could not touch the private memory, creating store-and-forward problems for the operating system. Fortunately, there were also interprocessor message buffers that lived outside the main memory space.
The main reason for the ETA-10's speed was the use of liquid cooling using liquid nitrogen to cool the logic components. Even though it was based on then-current CMOS technologies, the cooling allowed the CPU's to operate on a ~7ns cycle, so a fully-loaded ETA-10 was capable of about 4.5 GFLOPS. A slower, lower-cost air-cooled version, the ETA-10P (code named "Piper") was also marketed, but none were sold.
Only 25 ETA-10's were sold, and in April 1989 ETA was re-folded into CDC. Shortly thereafter CDC exited the supercomputer market.
