SAN JOSE, California — A white cursor blinks in the monitor’s top left corner. From beneath, a slab of machinery whirs, shudders and falls expectantly quiet.

Facing me is an original edition of the first IBM PC, a computer that made its debut the summer I was born. We ought to have some affinity for each other, I think. I want this relationship to work. But I’m not sure what to do. There is no mouse to shake and wake up the screen, no icon to click or touch.

Introduced 30 years ago, and once embedded in homes and offices across America, the IBM 5150 is the forebear of much of the technology I take for granted – the Mitochondrial Eve that eventually led to the sleek laptop computer on which I live so much of my life. As I sit at the IBM’s 80-column wide display, I half expect my fingers to know what to do with the machine’s clacky keyboard, guided by some subconscious aptitude distilled from living among the 5150’s distant offspring. Instead, the screen and I stare blankly back at each other, separated by decades of technological evolution.

“It has a 16 bit CPU, 8 bit memory bus, and ran at a solid 4.77 megahertz,” says Erik Klein from over my shoulder. “The original one had a motherboard which supported 16 to 64K. And you could put extension cards in it all the way up to 640K!”