The first electronic computer, ENIAC, weighed about 30 tonnes.
Why it is true
Built between 1943 and 1946, ENIAC occupied a room of 167 square metres and weighed approximately 30 tonnes. It used over 17,000 vacuum tubes and consumed 150 kilowatts of power. It was a thousand times faster than the electromechanical computers of the time.
Source: Smithsonian
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