Answer:
By the numbers: “The ENIAC contained 17,468 vacuum tubes, along with 70,000 resistors, 10,000 capacitors, 1,500 relays, 6,000 manual switches and 5 million soldered joints. It covered 1,800 square feet (167 square meters) of floor space, weighed 30 tons, consumed 160 kilowatts of electrical power.” More info