April 21, 2026
3 MIPS and a dream
20000 Gates and 20 MIPS [pdf]
From “20 MIPS” swagger to 3 MIPS reality — and the comments are loving the chaos
TLDR: A resurfaced Amdahl interview shows a bold plan for fast mainframes that delivered only 3 MIPS but still beat rivals. Comments split between history buffs dropping rare Mascor–IBM ACS links and jokesters memeing the “1990” tag, turning a tech time capsule into a lesson on big bets and bigger risks.
An old-school Amdahl interview just resurfaced, and the internet is clutching its pearls. The piece tells how Gene Amdahl bolted from IBM with a big idea—build a smaller, faster mainframe—and how the team shot for “20,000 gates and 20 MIPS” (speed bragging) but landed closer to 3 MIPS. And yet, they still beat rivals. Cue the nostalgia flood.
The comments? A glorious split. One user just deadpans “(1990)”, instantly turning the post into a timestamp meme. But the real mic drop comes from user bitsavers, who ties this story to deep-cut computer lore: a rare Mascor manual from ~1970, the “missing link” between IBM’s secretive Advanced Computing Systems (ACS) project and the engineers who later powered Amdahl. They add a cold-splash reality check: Mascor was one of many startups wiped out by the 1970 recession. Historians cheered; cynics called it the classic “dream big, ship small” tale.
Readers cackled at the wild details—designing chips on punch cards, running a hardware “simulator” the length of a freight train, and cramming in a whopping eight megabytes of memory (aka less than a selfie). The mood swings between awe at the grit and snark about the numbers. But the vibe is clear: even at 3 MIPS, this crew hustled—and the receipts are in bitsavers.
Key Points
- •Interview with early Amdahl engineers details the company’s origins and approach to innovation ahead of its sixth product generation.
- •Gene Amdahl founded Amdahl Corporation after leaving IBM to build purpose‑designed high‑end mainframes, emphasizing small, fast designs.
- •The Amdahl 470’s initial targets were framed as 20,000 gates and 20 MIPS; goals shifted to 12 MIPS, and the first implementation achieved about 3 MIPS.
- •Early development relied on self‑built tools running on IBM 1130s with punch cards, a router for artwork, and a large hardware logic simulator built from older technology.
- •The original Amdahl 470 supported up to eight megabytes of memory, and teams performed weekly engineering changes to iterate on design issues.