The new brand successfully got rid of the "plagiarism" of digital series brands such as 286, 386 and 486 by AMD and other companies, and established a brand-new leader image.
Coupled with the successful promotion of the Intel Inside program in the early 1990s, Intel has successfully changed from a company mainly supplying computer manufacturers to a brand directly facing consumers.
I don't know which genius translated Pentium into a domineering Pentium, which really surprised the audience.
With new products and brands, Intel is in high spirits and ready to dominate the world.
But no one expected that there was a Bug hidden inside this highly anticipated CPU!
The process of Bug discovery is also quite legendary, so we should start with a concept in mathematics.
As early as the Greek era, Euclid had proved that there were infinitely many prime numbers, and the larger the number, the more sparse the distribution of prime numbers.
Amazingly, although the distribution is sparse, as long as one prime number appears, another can be found nearby, such as 4 1 and 43, 10 1 and 103, 10007 and 10009.
Mathematicians have given these continuous prime numbers with a difference of 2 a name: twin prime numbers.
19 19, the Norwegian mathematician Vigo Buren proved an interesting thing. Even if there are infinitely many twin prime numbers, the sum of their reciprocal will converge to a constant, which is called "Brownian constant".
But this is a headache for mathematicians: they don't know whether this Brown constant is irrational or not.
With the appearance of computers, some people have come up with a unique trick: using the powerful computing power of computers to solve problems violently.
Thomas Nicely, a professor of mathematics at Lynchburg College in the United States, is one of them. His laboratory happens to be equipped with a new Pentium computer.
In order to prevent miscalculation, strict uses two algorithms to do double insurance. If the answer is different, there must be something wrong.
He began to calculate hopefully, but the result disappointed him: the results of the two algorithms are really different!
After in-depth study, it is beautifully found that the reciprocal of twin prime number 824 633 702 443 10 is miscalculated!
Well calculated with an old 486 computer, the answer is correct.
He recalculated with a Pentium computer, and the error reappeared.
Is there something wrong with your own program? Or is it the computer?
Very beautiful start to do the elimination method, eliminate the mistakes of your own code, Borland compiler and chipset. It took four months to finally find the source of the Bug: Pentium CPU.
1October 24th, 1994, 10, call the technical support department of Intel beautifully and tell them this problem. Intel said there would be a reply in a few days, but there has been no news since then.
There is a simple reason. Intel knew about this problem as early as June 1994: floating-point division operation (FDIV) error.
The FDIV of Pentium CPU introduces a new fast implementation method, which uses the hardware lookup table of 2048 items. However, due to an accident, five values were set incorrectly. They should be 2, but they are set to 0.
This Bug will only be triggered during high-precision calculation, which is difficult for ordinary users to encounter. Byte magazine estimates that the probability of error is one in nine billion.
Since the impact is not great, Intel's choice is to hide, quietly repair, and not disclose any details.
After all, millions of CPUs have been sold, and the loss of large-scale recall is too great.
Not that I can't!
Very good, who didn't get an answer, very depressed. 10 year 10 30th, he started to send emails to some IT celebrities and magazines, including Byte Magazine, PC Week, InfoWorld and PC Magazine.
This matter quickly fermented on the internet, and a large number of cattle people started the relay race of problem positioning:
The first player is well mentioned above.
The second best is Terje Mathis, who quickly confirmed Nicely's problem, and wrote a simple assembly test program and sent it to comp.sys.intel newsgroup (yes, not to mention the social network at that time, even BBS was not popular).
The third stick is Andreas Kaiser of Germany, who found 24 numbers, and their reciprocal can only get single-precision results on Pentium CPU.
The fourth is a professional who designs FPU (floating point unit), and Tim Coe, a semiconductor designer in Vitesse, California.
According to the clue of 24 numbers, he speculated that the Pentium CPU adopted the SRT algorithm with radix 4, which can generate a two-digit quotient in each clock cycle, making the speed twice as fast as the original.
Indeed, internal professionals are really powerful.
Fifth, there is a super Daniel, the father of MATLAB: Cliff Moeller.
Moeller summarized the previous data and found the rule of bugs.
Visible, made a mistake, can't hide. The more you try to hide it, the more people in the world will turn you upside down.
But so far, Intel Pentium, a hardware Bug, is still hovering in the technology circle, and it needs to wait for an important moment to break this circle.
1994165438+1On October 24th, two engineers of JPL (Jet Propulsion Laboratory, with Qian Xuesen as an important founder) learned of this Bug and suggested that the laboratory stop buying Pentium computers.
Pentium CPU, a Bug that was originally difficult to appear, suddenly became a hot topic in the streets.
Under the pressure of the media, Intel finally admitted the vulnerability of floating-point computing, but still insisted that it was not serious, and only replaced the CPU for those users who could prove that they were affected.
This attitude of trying to muddle through has aroused public anger and shaken consumers' confidence in Intel CPU.
Other manufacturers are also advancing with the times. IBM suspended the sale of personal computers equipped with Intel CPU, which led to a sharp drop in Intel's share price.
1994 65438+In February, the untenable Intel finally announced the recall of all defective processors.
This is also the first comprehensive recall of computer chips in history.
The price paid by Intel is $475 million, and the reputation loss is incalculable.
The story doesn't end here.
It is reasonable to say that there is something wrong with the hardware, which cannot be modified and can only be replaced.
But don't forget the group of geniuses we just mentioned, Cliff Moeller, Tim Coe, Peter Tang of Argonne National Laboratory, and several engineers who came to Intel. Together, they developed a very clever software repair method on February 5, 65438.
I won't go into details here, probably: under certain circumstances, both dividend and divisor can be multiplied by 15/ 16 to enter a safe state.
This hotfix has been sent to the newsgroup for everyone to use for free.
Cleve Moler asked the company to release a version of MATLAB that can detect and correct division errors, and immediately released a press release "MathWorks fixes Intel Pentium floating-point bugs".
Just as the Bug of Pentium was raging and was well known throughout the country, press releases appeared on fax machines of major media in the United States.
Cliff Moeller successfully implemented a perfect marketing. This year, his company MathWorks was only a small company with less than 250 people, and then it embarked on the fast lane and became a giant in this field.