There's something very funny about old minicomputer advertisements:
These are unlike any ads you see anymore!
Technology is today sold as something friendly and approachable. These adverisements are decidely not accessible. They try to capture something aspirational, something that echoes the old Apollo missions. The stare back is a call-to-action, a call to do something big. It says "Are you willing to take on a minicomputer and change your business?"
The style did change because this doesn't really work. Apple proved that. Steve Jobs based the design of the Apple ][ on a Braun blender. It was more approachable and felt like something you'd keep on a desk, in a living room, or on a kitchen counter.
Minicomputers, by contrast, look like science fiction devices:
But all the same, these advertisements are wild and fascinating.
You can read the original advertisements here.