What Was The Most Expensive Computer Of All Time?
Operational between 1958 and 1983, the Semi-Automatic Ground Environment (SAGE) computer was, and remains, the single most expensive computing system ever constructed. Developed for the the United States Airforce by IBM, SAGE was a Cold War-era behemoth designed to autonomously monitor America’s air space against air-based attack.
While neither IBM nor the government have ever released production costs on the secretive (and now decommissioned) project, civilian estimates put the total development cost at 8-12 billion dollars (60-90 billion dollars when adjusted for inflation). Although it’s important to note that this cost includes both the development of the computer system, the supporting equipment, and the bunkers to house it, even if the direct computer development cost was 1/10th the total project cost the SAGE computer system would still exceed the expense of any other computer system by several fold.
In addition to being the priciest computer system ever devised, the SAGE system also takes the prize for the heaviest (the complete system weighed over 250 tons) and the largest (composed of 56 AN/FSQ-T units, the total operating space was over 20,000 square feet).