Pentium flaw

electronics

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Last updated

July 19, 2026

Quick Summary

The Pentium flaw was a significant error discovered in Intel's Pentium microprocessor shortly after its 1993 release. This flaw involved a small segment of the chip's transistors that performed division incorrectly.1

Intel engineers identified the issue but initially chose not to disclose it. However, mathematician Thomas Nicely independently discovered the flaw. Despite initial resistance from Intel's CEO, the company was forced to recall the product after IBM announced it would not ship computers containing the faulty CPU. This recall cost Intel $475 million.1

The Pentium microprocessor was a key product for Intel, succeeding the 80486 and featuring advanced capabilities like parallel processing. It significantly boosted the performance of personal computers, enabling more demanding applications. The flaw, though costly, did not permanently derail Intel's dominance in the microprocessor market, largely due to the continued synergy between Intel chips and Microsoft's Windows operating system.12

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Intel
1990s: The Pentium microprocessor and Intel inside
…greatest mistake was the so-called Pentium flaw, in which an obscure segment among the Pentium CPU’s 3.1 million transistors performed division incorrectly. Company engineers discovered the problem after the product’s release in 1993 but decided to keep quiet and fix the problem in updates to the chip. But mathematician Thomas…
Read More
…greatest mistake was the so-called Pentium flaw, in which an obscure segment among the Pentium CPU’s 3.1 million transistors performed division incorrectly. Company engineers discovered the problem after the product’s release in 1993 but decided to keep quiet and fix the problem in updates to the chip. But mathematician Thomas…
Read More

twin prime conjecture
…Corporation when he discovered a flaw in the chip that was producing inconsistent results in his calculations of Brun’s constant. Negative publicity from the mathematics community led Intel to offer free replacement chips that had been modified to correct the problem. In 2010 Nicely gave a value for Brun’s constant…
Read More
…Corporation when he discovered a flaw in the chip that was producing inconsistent results in his calculations of Brun’s constant. Negative publicity from the mathematics community led Intel to offer free replacement chips that had been modified to correct the problem. In 2010 Nicely gave a value for Brun’s constant…
Read More