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IT HISTORY
The System Architect DEC Let Go — Who Built The Engine Running One Billion PCs
When minicomputer giant DEC dismissed David Cutler, Bill Gates wrote a blank check — and got the kernel that outlived both empires
The most dangerous illusion in software history is mistaking commercial luck for architectural permanence.
In the summer of 1980, 24-year-old Tim Paterson spent roughly six weeks assembling QDOS in a warehouse south of Seattle. Bill Gates bought it for $75,000, relabeled it MS-DOS, and shipped it on the IBM PC. That crude, temporary codebase secured Microsoft’s ticket to monopoly and filled its treasury with tens of millions of dollars.
By 1988, inside Microsoft’s Redmond headquarters, the 33-year-old Gates knew the uncomfortable truth: that six-week hack was leading Microsoft straight into a dead end.
A fragile fortune built on a six-week hack
MS-DOS was a single-tasking operating system with zero memory protection.
Its physical memory was boxed inside the 640 KB real-mode ceiling of the Intel 8086. In an enterprise office, if any third-party program misplaced a single pointer, the entire machine…
