It was CPU. It was all the rage around 1981-82 when I got out of the hobby as a teen and when I went back into my LCS several years later and asked for one, the owner chuckled and asked where I'd been, then handed me a Beckett magazine.
The RC thing really started to matter in the early 1980s due to the publications pushing it. Before that, RCs were usually multi-player cards and were considered less desirable for that reason. By the mid-1980s the RC thing was in full bloom, and that run of Ripken, Gwynn, Boggs, Sandberg, Mattingly and several others who faded away (1984 Donruss Joe Carter anyone?) reached its apex in 1989 with Griffey and Upper Deck. Those things traded like penny stocks, in bricks. I knew weekend warriors who went all-in early and grossed thousands of dollars a day flipping them. Then we got junk wax...
The biggest RC of them all was Michael Jordan. I remember walking past an entire table of 1986 Fleer around 1987 or so and derisively describing it as crap.
