In 1940s-1950s, computer used vacum tubes and they were huge and complex. The first general purpose electronic was ENIAC(Electronic Numerical Integrator and Computer). This first generation computer used digital , didn't operate with binary code and was reprogrammable to solve a complete range of computing problems.It was programmed using plugboards and switches, supporting input from an IBM card reader, and output to an IBM card punch. It took up 167 square meters, weighed 27 tons, and consuming 150 kilowatts of power. It used thousands of vacuum tubes, crystal diodes, relays, resistors, and capacitors.

Here is the picture about the first computer with many vacum tubes and cabel.