IBM Model M Keyboard

Model M value tracks the birth-certificate date and the state of the case: an early buckling-spring board with an unbleached shell is a different proposition from a yellowed later one. The IBM Model M is the keyboard that all other keyboards are measured against. First manufactured in 1985 by IBM (and later Lexmark), it uses a buckling spring mechanism that produces the most satisfying tactile feedback and audible click in keyboard history. The Model M was built like a tank — a steel backplate gives it serious heft, and many units from the late 80s are still in daily use four decades later.

The Model M is collectible because it is both a usable tool and a piece of computing history. Mechanical keyboard enthusiasts revere the buckling spring as the gold standard of typing feel, and no modern clone has perfectly replicated it. Early IBM-branded units (pre-1991 Lexmark takeover) carry a premium, and specific date codes from the original IBM Lexington factory are especially sought after. The keyboard also spawned the entire modern mechanical keyboard hobby.

When buying, test every key if possible — stuck or non-registering keys usually mean a bad membrane sheet, which is repairable but requires disassembly. Check the cable: original coiled SDL cables are preferred, and PS/2 models will need an active adapter for modern systems. Yellowing is cosmetic and can be addressed with retrobright. The real deal-breaker is a cracked barrel plate (the plastic sheet that holds the springs) — this is an expensive and difficult repair. Bolt-modded units, where the plastic rivets are replaced with screws, are actually more desirable since they indicate a refurbished and reinforced keyboard.