What is 1 hertz equal to? What is measured in hertz and gigahertz. Determining the presence of electromagnetic radiation

In the language, the abbreviation “Hz” is used to denote it; in English, the designation Hz is used for these purposes. At the same time, according to the rules of the SI system, if the abbreviated name of this unit is used, it should be followed by , and if the full name is used in the text, then with lowercase.

Origin of the term

The frequency unit adopted in the modern SI system received its name in 1930, when the International Electrotechnical Commission made a corresponding decision. It was associated with the desire to perpetuate the memory of the famous German scientist Heinrich Hertz, who made a great contribution to the development of this science, in particular in the field of electrodynamics research.

Meaning of the term

Hertz is used to measure the frequency of vibrations of any kind, so the scope of its use is very wide. For example, it is customary to measure sound frequencies, the beating of the human heart, and electrical oscillations in the number of hertz. magnetic field and other movements that are repeated at certain intervals. For example, the human heartbeat frequency in a calm state is about 1 Hz.

In essence, a unit in this measurement is interpreted as the number of oscillations performed by the analyzed object within one second. In this case, experts say that the oscillation frequency is 1 hertz. Respectively, large quantity vibrations per second corresponds to more of these units. Thus, from a formal point of view, the quantity denoted as hertz is the reciprocal of the second.

Significant frequency values are usually called high, and minor frequencies are called low. Examples of high and low frequencies can serve as sound vibrations of varying intensity. For example, frequencies in the range from 16 to 70 Hz form so-called bass sounds, that is, very low sounds, and frequencies in the range from 0 to 16 Hz are completely inaudible to the human ear. The highest sounds that a person can hear lie in the range from 10 to 20 thousand hertz, and sounds with more high frequency belong to the category of ultrasounds, that is, those that a person is not able to hear.

To denote higher frequency values, special prefixes are added to the designation “hertz”, designed to make the use of this unit more convenient. Moreover, such prefixes are standard for the SI system, that is, they are also used with other physical quantities. Thus, a thousand hertz is called “kilohertz”, a million hertz is called “megahertz”, a billion hertz is called “gigahertz”.

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1 megahertz [MHz] = 0.001 gigahertz [GHz]

Initial value

Converted value

hertz exahertz petahertz terahertz gigahertz megahertz kilohertz hectohertz dekahertz decihertz centihertz millihertz microhertz nanohertz picohertz femtohertz attohertz cycles per second wavelength in exameters wavelength in petameters wavelength in terameters wavelength in gigameters wavelength in megameters wavelength in kilometers wavelength in hectometers wavelength in decameters wavelength in meters wavelength in decimeters wavelength in centimeters wavelength in millimeters wavelength in micrometers Compton wavelength of an electron Compton wavelength of a proton Compton wavelength of a neutron revolutions per second revolutions per minute revolutions per hour revolutions per day

Thermal efficiency and fuel efficiency

More about frequency and wavelength

General information

Frequency

Frequency is a quantity that measures how often a particular periodic process is repeated. In physics, frequency is used to describe the properties of wave processes. Wave frequency is the number of complete cycles of the wave process per unit of time. The SI unit of frequency is hertz (Hz). One hertz is equal to one vibration per second.

Wavelength

There are many various types waves in nature, from wind-driven sea waves to electromagnetic waves. The properties of electromagnetic waves depend on the wavelength. Such waves are divided into several types:

Gamma rays with wavelengths up to 0.01 nanometers (nm).
X-rays with wavelength - from 0.01 nm to 10 nm.
Waves ultraviolet range, which have a length from 10 to 380 nm. They are invisible to the human eye.
Light in visible part of the spectrum with a wavelength of 380–700 nm.
Invisible to people infrared radiation with wavelengths from 700 nm to 1 millimeter.
Infrared waves are followed by microwave, with wavelengths from 1 millimeter to 1 meter.
The longest - radio waves. Their length starts from 1 meter.

This article is about electromagnetic radiation, and especially light. In it we will discuss how wavelength and frequency affect light, including the visible spectrum, ultraviolet and infrared radiation.

Electromagnetic radiation

Electromagnetic radiation is energy whose properties are both similar to those of waves and particles. This feature is called wave-particle duality. Electromagnetic waves consist of a magnetic wave and an electric wave perpendicular to it.

The energy of electromagnetic radiation is the result of the movement of particles called photons. The higher the frequency of radiation, the more active they are, and the more harm they can cause to the cells and tissues of living organisms. This happens because the higher the frequency of the radiation, the more energy they carry. Greater energy allows them to change the molecular structure of the substances they act on. This is why ultraviolet, x-ray and gamma radiation are so harmful to animals and plants. A huge part of this radiation is in space. It is also present on Earth, despite the fact that ozone layer The atmosphere around the Earth blocks most of it.

Electromagnetic radiation and the atmosphere

The earth's atmosphere allows only electromagnetic radiation to pass through at a certain frequency. Most gamma rays, x-rays, ultraviolet light, some infrared radiation and long radio waves are blocked by the Earth's atmosphere. The atmosphere absorbs them and does not let them pass further. Some electromagnetic waves, in particular short-wave radiation, are reflected from the ionosphere. All other radiation hits the Earth's surface. There is more radiation in the upper layers of the atmosphere, that is, further from the Earth's surface, than in the lower layers. Therefore, the higher you go, the more dangerous it is for living organisms to be there without protective suits.

The atmosphere allows a small amount of ultraviolet light to reach the Earth, and it is harmful to the skin. It is because of ultraviolet rays that people get sunburned and can even get skin cancer. On the other hand, some rays transmitted by the atmosphere are beneficial. For example, infrared rays that hit the Earth's surface are used in astronomy - infrared telescopes monitor the infrared rays emitted by astronomical objects. The higher you are from the Earth's surface, the more infrared radiation there is, which is why telescopes are often installed on mountain tops and other elevations. Sometimes they are sent into space to improve the visibility of infrared rays.

Relationship between frequency and wavelength

Frequency and wavelength are inversely proportional to each other. This means that as the wavelength increases, the frequency decreases and vice versa. It is easy to imagine: if the oscillation frequency of the wave process is high, then the time between oscillations is much shorter than for waves whose oscillation frequency is lower. If you imagine a wave on a graph, the distance between its peaks will be smaller, the more oscillations it makes in a certain period of time.

To determine the speed of propagation of a wave in a medium, it is necessary to multiply the frequency of the wave by its length. Electromagnetic waves in a vacuum always travel at the same speed. This speed is known as the speed of light. It is equal to 299 792 458 meters per second.

Light

Visible light is electromagnetic waves with a frequency and wavelength that determine its color.

Wavelength and color

The shortest wavelength of visible light is 380 nanometers. It is the color violet, followed by blue and cyan, then green, yellow, orange and finally red. White light consists of all colors at once, that is, white objects reflect all colors. This can be seen using a prism. The light entering it is refracted and arranged into a stripe of colors in the same sequence as in a rainbow. This sequence is from colors with the shortest wavelength to the longest. The dependence of the speed of light propagation in a substance on the wavelength is called dispersion.

Rainbows are formed in a similar way. Drops of water scattered in the atmosphere after rain behave in the same way as a prism and refract each wave. The colors of the rainbow are so important that many languages have mnemonics, that is, a technique for remembering the colors of the rainbow that is so simple that even children can remember them. Many children who speak Russian know that “Every hunter wants to know where the pheasant sits.” Some people come up with their own mnemonics, and this is a particularly useful exercise for children, since by coming up with their own method of remembering the colors of the rainbow, they will remember them faster.

The light to which the human eye is most sensitive is green, with a wavelength of 555 nm in bright environments and 505 nm in twilight and darkness. Not all animals can distinguish colors. Cats, for example, do not have developed color vision. On the other hand, some animals see colors much better than humans. For example, some species see ultraviolet and infrared light.

Reflection of light

The color of an object is determined by the wavelength of light reflected from its surface. White objects reflect all waves of the visible spectrum, while black objects, on the contrary, absorb all waves and reflect nothing.

One of the natural materials with a high dispersion coefficient is diamond. Properly processed diamonds reflect light from both the outer and inner faces, refracting it, just like a prism. It is important that most of this light is reflected upward, towards the eye, and not, for example, downward, inside the frame, where it is not visible. Due to their high dispersion, diamonds shine very beautifully in the sun and at artificial lighting. Glass cut the same way as a diamond also shines, but not as much. This is because, due to their chemical composition, diamonds reflect light much better than glass. The angles used when cutting diamonds are of utmost importance because angles that are too sharp or too obtuse either prevent light from reflecting off the interior walls or reflect light into the setting, as shown in the illustration.

Spectroscopy

Spectral analysis or spectroscopy is sometimes used to determine the chemical composition of a substance. This method is especially good if a chemical analysis of a substance cannot be carried out by working with it directly, for example, when determining the chemical composition of stars. Knowing what electromagnetic radiation a body absorbs, one can determine what it consists of. Absorption spectroscopy, which is one of the branches of spectroscopy, determines what radiation is absorbed by the body. Such an analysis can be done at a distance, so it is often used in astronomy, as well as in working with toxic and dangerous substances.

Determining the presence of electromagnetic radiation

Visible light, like all electromagnetic radiation, is energy. The more energy is emitted, the easier it is to measure this radiation. The amount of energy emitted decreases as the wavelength increases. Vision is possible precisely because people and animals recognize this energy and feel the difference between radiation with different wavelengths. Electromagnetic radiation of different lengths is perceived by the eye as different colors. Not only the eyes of animals and people work according to this principle, but also technologies created by people for processing electromagnetic radiation.

Visible light

People and animals see a wide spectrum of electromagnetic radiation. Most people and animals, for example, react to visible light, and some animals also respond to ultraviolet and infrared rays. The ability to distinguish colors is not present in all animals - some only see the difference between light and dark surfaces. Our brain determines color this way: photons of electromagnetic radiation enter the eye onto the retina and, passing through it, excite the cones, the photoreceptors of the eye. As a result, a signal is transmitted through the nervous system to the brain. In addition to cones, the eyes also have other photoreceptors, rods, but they are not able to distinguish colors. Their purpose is to determine the brightness and intensity of light.

There are usually several types of cones in the eye. Humans have three types, each of which absorbs photons of light within certain wavelengths. When they are absorbed, a chemical reaction occurs, as a result of which nerve impulses with information about the wavelength are sent to the brain. These signals are processed by the visual cortex of the brain. This is the area of the brain responsible for the perception of sound. Each type of cone is responsible for only wavelengths of a certain length, so to get a complete picture of color, the information received from all cones is added together.

Some animals have even more types of cones than humans. For example, some species of fish and birds have four to five types. Interestingly, females of some animals have more types of cones than males. Some birds, such as gulls, that catch prey in or on the surface of the water, have yellow or red droplets of oil inside their cones that act as a filter. This helps them see more colors. The eyes of reptiles are designed in a similar way.

Infrared light

Snakes, unlike people, have not only visual receptors, but also sensory organs that respond to infrared radiation. They absorb the energy of infrared rays, that is, they react to heat. Some devices, such as night vision devices, also respond to the heat generated by the infrared emitter. Such devices are used by the military, as well as to ensure the safety and security of premises and territory. Animals that see infrared light, and devices that can recognize it, see not only objects that are in their field of vision on this moment, but also traces of objects, animals, or people who were there before, if too much time has not passed. For example, snakes can see if rodents have been digging a hole in the ground, and police officers who use night vision devices can see if evidence of a crime, such as money, drugs, or something else, has recently been hidden in the ground. Devices for recording infrared radiation are used in telescopes, as well as for checking containers and cameras for leaks. With their help, the location of the heat leak can be clearly seen. In medicine, infrared light images are used for diagnostic purposes. In the history of art - to determine what is depicted under the top layer of paint. Night vision devices are used to protect premises.

Ultraviolet light

Some fish see ultraviolet light. Their eyes contain pigment that is sensitive to ultraviolet rays. Fish skin contains areas that reflect ultraviolet light, invisible to humans and other animals - which is often used in the animal kingdom to mark the sex of animals, as well as for social purposes. Some birds also see ultraviolet light. This skill is especially important during the mating season, when birds are looking for potential mates. The surfaces of some plants also reflect ultraviolet light well, and the ability to see it helps in finding food. In addition to fish and birds, some reptiles see ultraviolet light, such as turtles, lizards and green iguanas (illustrated).

The human eye, like animal eyes, absorbs ultraviolet light but cannot process it. In humans, it destroys cells in the eye, especially in the cornea and lens. This, in turn, causes various diseases and even blindness. Although ultraviolet light is harmful to vision, small amounts are needed by humans and animals to produce vitamin D. Ultraviolet radiation, like infrared, is used in many industries, for example in medicine for disinfection, in astronomy for observing stars and other objects and in chemistry for solidifying liquid substances, as well as for visualization, that is, for creating diagrams of the distribution of substances in a certain space. With the help of ultraviolet light, counterfeit banknotes and passes are detected if they have characters printed on them with special ink that can be recognized using ultraviolet light. In the case of document forgery, the UV lamp does not always help, since criminals sometimes use the real document and replace the photo or other information on it, so that the UV lamp marking remains. There are also many other uses for ultraviolet light.

Color blindness

Due to vision defects, some people are unable to distinguish colors. This problem is called color blindness or color blindness, named after the person who first described this vision feature. Sometimes people only don't see colors at a certain wavelength, and sometimes they don't see colors at all. Often the cause is underdeveloped or damaged photoreceptors, but in some cases the problem is damage to neural pathways such as the visual cortex, where color information is processed. In many cases, this condition creates inconvenience and problems for people and animals, but sometimes the inability to distinguish colors, on the contrary, is an advantage. This is confirmed by the fact that, despite many years of evolution, many animals do not have developed color vision. People and animals that are colorblind can, for example, clearly see the camouflage of other animals.

Despite the benefits of color blindness, it is considered a problem in society, and some professions are closed to people with color blindness. They usually cannot obtain full rights to fly an aircraft without restrictions. In many countries, these people also have restrictions on their driving license, and in some cases they cannot get a license at all. Therefore, they cannot always find a job where they need to drive a car, airplane, or other vehicles. They also have difficulty finding jobs where the ability to identify and use colors is important. For example, they find it difficult to become designers, or to work in an environment where color is used as a signal (for example, of danger).

Work is underway to create more favorable conditions for people with color blindness. For example, there are tables in which colors correspond to signs, and in some countries these signs are used in institutions and public places along with color. Some designers do not use or limit the use of color to convey important information in his works. Instead of, or along with, color, they use brightness, text, and other means of highlighting information so that even color-blind people can fully receive the information the designer is conveying. In most cases, people with color blindness cannot distinguish between red and green, so designers sometimes replace the combination of “red = danger, green = okay” with red and blue. Majority operating systems They also allow you to adjust colors so that people with color blindness can see everything.

Color in machine vision

Color computer vision is a fast-growing branch of artificial intelligence. Until recently, most of the work in this area was done with monochrome images, but now more and more scientific laboratories are working with color. Some algorithms for working with monochrome images are also used for processing color images.

Application

Computer vision is used in a number of industries, such as controlling robots, self-driving cars, and unmanned aerial vehicles. It is useful in the field of security, for example, for identifying people and objects from photographs, for searching databases, for tracking the movement of objects depending on their color, and so on. Determining the location of moving objects allows a computer to determine the direction a person is looking or follow the movement of cars, people, hands, and other objects.

To correctly identify unfamiliar objects, it is important to know about their shape and other properties, but information about color is not so important. When working with familiar objects, color, on the contrary, helps to recognize them faster. Working with color is also convenient because color information can be obtained even from low-resolution images. Recognizing the shape of an object, as opposed to its color, requires high resolution. Working with color instead of the shape of an object allows you to reduce image processing time and use fewer computer resources. Color helps to recognize objects of the same shape, and can also be used as a signal or sign (for example, red is a danger signal). In this case, you do not need to recognize the shape of this sign or the text written on it. There are many interesting examples of the use of color on the YouTube website. machine vision.

Processing color information

The photos that the computer processes are either uploaded by users or taken by the built-in camera. The process of digital photography and video shooting is well mastered, but the processing of these images, especially in color, is associated with many difficulties, many of which have not yet been resolved. This is due to the fact that color vision in humans and animals is very complex, and creating computer vision like human vision is not easy. Vision, like hearing, is based on adaptation to the environment. The perception of sound depends not only on the frequency, sound pressure and duration of the sound, but also on the presence or absence of other sounds in the environment. The same is with vision - the perception of color depends not only on the frequency and wavelength, but also on the characteristics of the environment. For example, the colors of surrounding objects affect our perception of color.

From an evolutionary point of view, such adaptation is necessary to help us get used to the environment and stop paying attention to insignificant elements, and direct our full attention to what is changing in the environment. This is necessary in order to more easily notice predators and find food. Sometimes optical illusions occur due to this adaptation. For example, depending on the color of the surrounding objects, we perceive the color of two objects differently, even when they reflect light with the same wavelength. The illustration shows an example of such an optical illusion. The brown square at the top of the image (second row, second column) appears lighter than the brown square at the bottom of the image (fifth row, second column). In fact, their colors are the same. Even knowing this, we still perceive them as different colors. Because our perception of color is so complex, it is difficult for programmers to describe all these nuances in computer vision algorithms. Despite these difficulties, we have already achieved a lot in this area.

Unit Converter articles were edited and illustrated by Anatoly Zolotkov

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1 gigahertz [GHz] = 1000000000 hertz [Hz]

Initial value

Converted value

More about frequency and wavelength

General information

Frequency

Wavelength

There are many different types of waves in nature, from wind-driven sea waves to electromagnetic waves. The properties of electromagnetic waves depend on the wavelength. Such waves are divided into several types:

Gamma rays with wavelengths up to 0.01 nanometers (nm).
X-rays with wavelength - from 0.01 nm to 10 nm.
Waves ultraviolet range, which have a length from 10 to 380 nm. They are invisible to the human eye.
Light in visible part of the spectrum with a wavelength of 380–700 nm.
Invisible to people infrared radiation with wavelengths from 700 nm to 1 millimeter.
Infrared waves are followed by microwave, with wavelengths from 1 millimeter to 1 meter.
The longest - radio waves. Their length starts from 1 meter.

Electromagnetic radiation

The energy of electromagnetic radiation is the result of the movement of particles called photons. The higher the frequency of radiation, the more active they are, and the more harm they can cause to the cells and tissues of living organisms. This happens because the higher the frequency of the radiation, the more energy they carry. Greater energy allows them to change the molecular structure of the substances they act on. This is why ultraviolet, x-ray and gamma radiation are so harmful to animals and plants. A huge part of this radiation is in space. It is also present on Earth, despite the fact that the ozone layer of the atmosphere around the Earth blocks most of it.

Electromagnetic radiation and the atmosphere

Relationship between frequency and wavelength

Light

Visible light is electromagnetic waves with a frequency and wavelength that determine its color.

Wavelength and color

Reflection of light

One of the natural materials with a high dispersion coefficient is diamond. Properly processed diamonds reflect light from both the outer and inner faces, refracting it, just like a prism. It is important that most of this light is reflected upward, towards the eye, and not, for example, downward, inside the frame, where it is not visible. Due to their high dispersion, diamonds shine very beautifully in the sun and under artificial light. Glass cut the same way as a diamond also shines, but not as much. This is because, due to their chemical composition, diamonds reflect light much better than glass. The angles used when cutting diamonds are of utmost importance because angles that are too sharp or too obtuse either prevent light from reflecting off the interior walls or reflect light into the setting, as shown in the illustration.

Spectroscopy

Determining the presence of electromagnetic radiation

Visible light

Infrared light

Snakes, unlike people, have not only visual receptors, but also sensory organs that respond to infrared radiation. They absorb the energy of infrared rays, that is, they react to heat. Some devices, such as night vision devices, also respond to the heat generated by the infrared emitter. Such devices are used by the military, as well as to ensure the safety and security of premises and territory. Animals that see infrared light, and devices that can recognize it, see not only objects that are in their field of vision at the moment, but also traces of objects, animals, or people that were there before, if not too much time has passed. a lot of time. For example, snakes can see if rodents have been digging a hole in the ground, and police officers who use night vision devices can see if evidence of a crime, such as money, drugs, or something else, has recently been hidden in the ground. Devices for recording infrared radiation are used in telescopes, as well as for checking containers and cameras for leaks. With their help, the location of the heat leak can be clearly seen. In medicine, infrared light images are used for diagnostic purposes. In the history of art - to determine what is depicted under the top layer of paint. Night vision devices are used to protect premises.

Ultraviolet light

Color blindness

Work is underway to create more favorable conditions for people with color blindness. For example, there are tables in which colors correspond to signs, and in some countries these signs are used in institutions and public places along with color. Some designers do not use or limit the use of color to convey important information in their work. Instead of, or along with, color, they use brightness, text, and other means of highlighting information so that even color-blind people can fully receive the information the designer is conveying. In most cases, people with color blindness cannot distinguish between red and green, so designers sometimes replace the combination of “red = danger, green = okay” with red and blue. Most operating systems also allow you to adjust colors so that people with color blindness can see everything.

Color in machine vision

Application

Processing color information

Unit Converter articles were edited and illustrated by Anatoly Zolotkov

Gigahertz taken, progress continues

And yet, processor life used to be more fun. About a quarter of a century ago, humanity crossed the 1 kHz barrier, and this dimension disappeared from the processor lexicon. The “power” of the processor began to be calculated in megahertz clock frequency (which, strictly speaking, is incorrect). Just three years ago, every 100 MHz step to increase the clock frequency was celebrated as a real event: with lengthy marketing artillery preparation, technological presentations and, in the end, a celebration of life. This was the case until the frequency of “desktop” processors reached 600 MHz (when the Mercedes namesake was mentioned in vain in every publication), and 0.18 microns became the main technology for producing chips. Then it became “uninteresting”: clock frequency increases occurred monthly, and at the end of last year, Intel completely “undermined” the information market by simultaneously announcing 15 new processors. Fifteen silicon microsensations fell on our heads like a lump, and the overall festive spirit of the event was lost in the examination of the features of each presented chip. Therefore, it is not surprising that the two leading manufacturers of PC processors (Intel and AMD) too casually exceeded the 1 GHz bar, pretending that nothing special had happened. In the heap of Internet comments, there was only one fanciful comparison with breaking the sound barrier, and so - no fireworks or champagne. This is understandable: the plans of the developers have long been directed towards the beyond-gigahertz space. We will see an Intel Willamette crystal with a clock frequency of 1.3-1.5 GHz in the second half of this year, and we will talk about the features of the architecture, and not about cycles per second.

In my memory, the coveted gigahertz was actively discussed more than a year ago, when on a hot Californian morning in the winter of 1999, Albert Yu demonstrated a Pentium III 0.25 micron, operating at a frequency of 1002 MHz. Under the general applause of the audience, it was somehow forgotten that that demonstration resembled a magic trick. Later it turned out that the processor was “overclocked” in a cryogenic installation. There is even indirect evidence that the refrigerator was a serial installation from KryoTech. One way or another, they forgot about gigahertz for a year, although processors came quite close to this frequency. It is curious that in the winter of 2000, the chairman of the board of directors of Intel, the legendary Andy Grove, with the assistance of Albert Yu, again repeated the tried and tested Intel trick. At the IDF Spring'2000 forum, he demonstrated a test sample of the Intel Willamette processor operating at a clock frequency of 1.5 GHz. One and a half billion cycles per second - and all at room temperature! It's gratifying that Willamette is also a microprocessor with a new architecture, and not just a slightly improved Pentium III. But more on this below.

AMD has already had its own marketing gigahertz for a long time. The company officially cooperates with the “lords of the cold” from KryoTech, and the Athlon turned out to be quite a promising processor for overclocking in extreme cooling conditions. A gigahertz solution based on a cooled Athlon 850 MHz was available for sale back in January.

The marketing situation heated up somewhat when AMD began shipping limited quantities of room-temperature 1 GHz Athlon processors in early March. There was nothing to do, and Intel had to pull out an ace from its sleeve - Pentium III (Coppermine) 1 GHz. Although the release of the latter was planned for the second half of the year. But it’s no secret that breaking the gigahertz barrier is premature for both AMD and Intel. But they so wanted to be first. One can hardly envy two respectable companies who are running around the only chair with the number 1 and waiting in horror for the music to stop. AMD just managed to sit down first - and that doesn't mean anything else. Like in astronautics: the USSR was the first to launch people, and the “second” Americans began to fly more often (and cheaper). And vice versa: they went to the moon, and we said “fi,” and all the enthusiasm disappeared. However, the clock frequency race has long had a purely marketing motive: people, as you know, tend to buy megahertz rather than performance indices. The clock speed of the processor, as before, is a matter of prestige and a bourgeois indicator of the “sophistication” of a computer.

Another growing player in the microprocessor market, the Taiwanese company VIA, officially presented its first child a month ago. The microprocessor, previously known under the code name Joshua, received the very original name Cyrix III and began to compete with Celeron from below, in the niche of the cheapest computers. Of course, in the next year he will not see gigahertz frequencies like his ears, but this “desktop” chip is interesting by the very fact of its existence in a hostile environment.

In this review, as always, we will talk about new products and plans of leading developers of microprocessors for PCs, without regard to whether they have overcome the gigahertz selective barrier.

Intel Willamette - new 32-bit chip architecture

Intel's 32-bit processor, codenamed Willamette (named after a 306-kilometer river in Oregon), will hit the market in the second half of this year. Based on a new architecture, it will be the most powerful Intel processor for desktop systems, and its starting frequency will be significantly higher than 1 GHz (1.3-1.5 GHz is expected). Deliveries of processor test samples to OEM manufacturers have been ongoing for almost two months. The Willamette chipset is codenamed Tehama.

What is hidden under the mysterious term “new architecture”? For starters, support for an external clock frequency of 400 MHz (that is, the frequency system bus). This is three times faster than the vaunted 133 MHz supported by modern Pentium III class processors. In fact, 400 MHz is the resulting frequency: that is, the bus has a frequency of 100 MHz, but is capable of transmitting four pieces of data per cycle, which gives a total of 400 MHz. The bus will use a data exchange protocol similar to that implemented by the P6 bus. The data transfer speed of this 64-bit synchronous bus is 3.2 GB/s. For comparison: the GTL+ 133 MHz bus (the one used by modern Pentium IIIs) has a throughput of slightly more than 1 GB/s.

The second distinctive feature of Willamette is support for SSE-2 (Streaming SIMD Extensions 2). This is a set of 144 new instructions to optimize your experience with video, encryption, and Internet applications. SSE-2 is naturally compatible with SSE, first implemented in Pentium III processors. Therefore, Willamette will be able to successfully use hundreds of applications designed with SSE in mind. Willamette itself uses 128-bit XMM registers to support both integer and floating point operations. Without going into details, the task of SSE2 is to compensate for the unit of floating point operations that is not the strongest on the market. If SSE2 is supported by third-party software manufacturers (Microsoft is both in favor), no one will notice the substitution against the backdrop of increased productivity.

And finally, the third key feature of Willamette is deeper pipelining. Instead of 10 stages, 20 are now used, which can significantly increase overall performance when processing certain complex mathematical applications and increase the clock frequency. True, a “deep” pipeline is a double-edged sword: the processing time of an operation is sharply reduced, but the increasing delay time when processing interdependent operations can “compensate” for the increase in pipeline productivity. To prevent this from happening, the developers had to increase the intelligence of the pipeline - increase the accuracy of transition prediction, which exceeded an average of 90%. Another way to improve the efficiency of a long pipeline is to prioritize (order) instructions in the cache. The function of the cache in this case is to arrange instructions in the order in which they should be executed. This is somewhat reminiscent of defragmenting a hard drive (only inside the cache).

Cache is a cache, but the greatest criticism for a long time has been the performance of the integer calculation unit in modern processors. The integer capabilities of processors are especially critical when running office applications (all sorts of Word and Excel). From year to year, both the Pentium III and Athlon showed simply ridiculous performance gains in integer calculations as the clock frequency increased (by a few percent). Willamette implements two integer operations modules. What is known about them so far is that each is capable of executing two instructions per clock cycle. This means that at a core frequency of 1.3 GHz, the resulting integer module frequency is equivalent to 2.6 GHz. And, I emphasize, there are two such modules. Which allows you to perform, in fact, four operations with integers per clock cycle.

There is no mention of cache size in the Willamette preliminary specification published by Intel. But there are “leaks” indicating that the L1 cache will be 256 KB in size (Pentium II/III has a 32 KB L1 cache - 16 KB for data and 16 KB for instructions). The same aura of mystery surrounds the L2 cache size. The most likely option is 512 KB.

The Willamette processor, according to some reports, will be supplied in packages with a matrix-pin arrangement of contacts for a Socket-462 socket.

AMD Athlon: 1.1 GHz demo, 1 GHz shipping

As if making up for the previous strategy of following the leader, AMD quickly thumbed its nose at the entire computer industry by demonstrating an Athlon processor with a clock frequency of 1.1 GHz (more precisely, 1116 MHz) at the beginning of winter. Everyone decided he was joking. They say, well, it has successful processors, but everyone knows how long the time lag is between demonstration and mass production. But that was not the case: a month later, Advanced Micro Devices began serial deliveries of Athlon processors with a clock frequency of 1 GHz. And all doubts about their real availability were dispelled by Compaq and Gateway, which offered elite systems based on these chips. The price, of course, did not leave a particularly pleasant impression. The gigahertz Athlon costs about $1,300 in batches of a thousand pieces. But it has quite nice younger brothers: Athlon 950 MHz ($1000) and Athlon 900 MHz ($900). However, there are few such processors, which is why the prices are sky-high.

The previously demonstrated Athlon 1116 MHz was remarkable in itself. Design standards are 0.18 microns, copper connections are used, heat dissipation is normal: it operates at room temperature with a conventional active radiator. But, as it turned out, it was not just an Athlon (it “just” has aluminum interconnects), but an Athlon Professional (code name Thunderbird). The actual appearance of such a processor on the market is expected only in the middle of the year (presumably in May). Only the frequency will be lower, and it will not cost “gigahertz dollars”, but noticeably cheaper.

Currently, not much is known about the Athlon processor based on the Thunderbird core. It will use not Slot A (like modern versions of Athlon from 500 MHz), but a matrix connector Socket A. Accordingly, the processor case will be “flat” and not a massive “vertical” cartridge. It is expected that by the summer processors based on the Thunderbird core will be released with clock frequencies from 700 to 900 MHz, and gigahertz will appear a little later. In general, given the rate of decline in prices for new processors, it is becoming quite possible to purchase an entry-level computer based on an Athlon 750 MHz or so for the New Year.

On the other hand, the main contender for low-end computers in the AMD line remains the yet unannounced processor based on the Spitfire core. It is assigned the role of a junior competitor to Intel Celeron. Spitfire will be packaged for installation in a Socket A processor socket (power supply - 1.5 V), and its clock frequency can reach 750 MHz by the beginning of autumn.

IBM's multi-gigahertz ambitions in brief

While the whole world is rejoicing in the old fashioned way when the gigahertz is gained, IBM is talking about technology that allows chips to gain gigahertz per year. At least 4.5 GHz is quite possible with existing semiconductor production technologies. So, according to IBM, the IPCMOS (Interlocked Pipelined CMOS) technology it developed will make it possible in three years to ensure mass production of chips with a clock frequency of 3.3-4.5 GHz. At the same time, power consumption will be reduced by a factor of two compared to the parameters of modern processors. The essence of the new processor architecture is the use of distributed clock pulses. Depending on the complexity of the task, one or another processor block will operate at a higher or lower clock frequency. The idea was obvious: all modern processors use a centralized clock frequency - all core elements, all computing units are synchronized with it. Roughly speaking, until all operations on one “turn” are completed, the processor will not begin the next one. As a result, slow operations hold back fast ones. In addition, it turns out that if you need to knock out a dusty carpet, you have to shake the whole house. A decentralized mechanism for supplying a clock frequency, depending on the needs of a particular block, allows the fast blocks of the microcircuit not to wait for slow operations to be processed in other blocks, but, relatively speaking, to do their own thing. As a result, overall energy consumption is reduced (you only need to shake the carpet, not the whole house). IBM engineers are absolutely right when they say that increasing synchronous clock speeds will become increasingly difficult from year to year. In this case, the only way is to use a decentralized clock frequency supply or completely switch to fundamentally new (quantum, probably) technologies for creating microcircuits. Because of this name, it’s tempting to classify it in the same class as the Pentium III. But this is a mistake. VIA itself positions it as a competitor to the Intel Celeron, a processor for entry-level systems. But this also turned out to be an overly arrogant act.

However, let's start with the advantages of the new processor. It is designed for installation in a Socket 370 processor socket (like Celeron). However, unlike Celeron, Cyrix III supports an external clock frequency (system bus frequency) not 66 MHz, but 133 MHz - like the most modern Pentium III of the Coppermine family. The second key advantage of the Cyrix III is the on-chip second-level cache (L2) with a capacity of 256 KB - like the new Pentium III. The first level cache is also large (64 KB).

And finally, the third advantage is support for the AMD Enhanced 3DNow! set of SIMD commands. This is truly the first example of 3Dnow integration! for Socket 370 processors. AMD multimedia instructions are already widely supported by software manufacturers, which will at least partially help compensate for the processor's speed lag in graphics and gaming applications.

This is where all good things end. The processor is produced using 0.18-micron technology with six layers of metallization. At the time of release, the fastest Cyriх III had a Pentium rating of 533. The actual core clock speed is noticeably lower, so since the time of independent Cyrix, it has labeled its processors with “ratings” in relation to clock frequencies processors Pentium, Pentium II, and later Pentium III. It would be better if they counted from Pentium: the figure would be more impressive.

The head of VIA, Wen Chi Chen (in the past, by the way, was an Intel processor engineer) was initially going to oppose Celeron to the low price of Cyrix III. How successful this was - judge for yourself. Cyrix III PR 500 starts at $84, and Cyrix III PR533 starts at $99. In short, Celeron sometimes costs less. The first tests of the processor (carried out, of course, not in Russia) showed that its performance in office applications (where the emphasis is on integer calculations) is not much inferior to Celeron, but in multimedia applications the gap is obvious. Of course, not in favor of Cyrix III. Well, the first damn thing is lumpy. However, VIA also has an integrated Samuel processor in reserve, built on the IDT WinChip4 core. The result may be better there.

Alpha will also receive a well-deserved gigahertz

Compaq (owner of part of the DEC legacy, including the Alpha processor) intends to release a 1 GHz version of the Alpha 21264 server RISC processor in the second half of the year. And its next chip - Alpha 21364 - even starts from this threshold frequency. In addition, the improved version of Alpha will be equipped with a 1.5 MB L2 cache and a Rambus memory controller.

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