Action Comics, Vol. 1 #514B (1980) Newsstand

Countdown of The Killer Computer! / Sunspotter's Crime Collection!
Supes returns from a mission to find the trains have collided and are falling off the rails. On saving the passengers he notes it was a computer failure which set it up. Around Metropolis thousands of computers are failing and he spends time fixing them but then finds missles are about to destroy Moscow and the US. 
Release Date: 1980