Pentium FDIV Bug
In 1988, Intel began development on the original Pentium, which was also called the P5. They had intended to learn in 1992 but was eventually launched in 1993. Upon its launch the Pentium came in 60 and 66 MHz variations and it was initially priced between US$878 AND US$964 respectfully per unit. Adverts put out by Intel promised consumers that the processor would make their computers run faster and it outperformed Intel’s top-of-the-line 486-based DX4 in many disciplines. The name Pentium was chosen as it came from the Latin pente (five) with the Latin ending “ium” and because their original choices that were just two series of numbers were uncopyrightable (<-- this word is one of the few in the English language with no repeated words and means exactly as you think it means: something that can’t be copyrighted). The choice of five/ pente was to indicate it being the fifth CPU in the x86 series.
Then suddenly, something went wrong!
It all went wrong when the professor of Mathematics at Lynchburg College, Thomas R. Nicely, discovered that there was a bug in the processor in 1994. This bug caused the processor to return incorrect binary filtering point results when dividing certain pairs of high precision numbers. While most users rarely encountered it in specific circumstances, it could lead to significant deviate (meaning to stray away from the norm) from correct output values. A frequently given example is the division of 4,195,835 by 3,145,727. To explain the technical stuff in a simple way (In English as those listening into a nerdy character in a 2000s movie or tv show despite English already being used before the suggestion is prompted), here’s what we need to know:
• The Issue: Intel wanted their computer chips to be able to divide numbers more quickly. It can take some time to split numbers, especially floating-point numbers. They made the decision to enhance this procedure.
• The Old Way: Intel's chips formerly employed a technique known as the "shift-and-subtract division algorithm". It wasn't very quick, but it did the trick.
• The Novel Approach: Intel substituted the outdated technique with an algorithm known as the "Sweeney, Robertson, and Tocher (SRT) algorithm." This new algorithm was quicker and more intelligent.
• How It Operates: - More work might be completed faster by the SRT algorithm. It was able to determine two bits of the division result per every clock cycle (the chip's equivalent of a heartbeat).
• In contrast, the algorithm of the outdated 486 chip could only process one bit every clock cycle.
• The Bug: Regrettably, an error occurred during the SRT algorithm's fabrication of the chips. The "programmable logic array" of the chip (which functions much like its brain) had five crucial values that were incorrectly set when it was manufactured.
• These mistakes accumulated and caused issues since the SRT algorithm is recursive, meaning it divides data into smaller pieces until it finds the solution. To put it another way, Intel intended to divide data more quickly, so they developed a new algorithm, but some errors in the chip-making process led to problems.
According to Byte magazine, 1 in 9 billion floating-point divisions with arbitrary parameters would yield unreliable results. As a result of this flaw, Intel launched the first-ever comprehensive processor recall, which involved all affected chips. The expense of replacing and depreciating these microprocessors was high for the corporation. It's still a significant moment in the history of hardware defects in computers!
If you think that was humiliating, just imagine yourself. You're an employee of Intel who has a family at home, complete with, let's say, around like two or three kids. One of them (or maybe all of them or even just like two of them depending on how many this employee had) come across a new cartoon on the television where a teenager was gifted a computer processor for Christmas, only for that computer processor to turn them into a blue skinned, raven haired, red jumpsuit wearing superhero (the teen in question had got the processor, not the Intel employees kids). If this programme rings any bells for those who grew up in the 1990s and early 2000s, then I just described the plot of the Steven Spielberg cartoon Freakazoid! Whose origins were a nod to the Pentium FDIV bug. If I have confused my younger audience about this character, then they just need to see Teen Titans Go! Episode Hugbees and then they will be familiar with the character of Freakazoid or just look up clips on YouTube with their parents/ guardians.