Comparison different types storage media
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Introduction
1. Magnetic storage
1.1. Drives on magnetic disks
1.2 Hard disk drives
2. Types of magnetic carriers
2.1 Flexible magnetic disks
2.2 External hard drives on the HDD
3. Optical technologies
3.1 CDs
In the end, it's time to see what we can do to minimize the possibility of damage hard drive. When buying such a device you need to take preventive measures. Most users ask the same question: which brand of hard drives is the best and most reliable? From the perspective of a technical specialist, a brand can not be uniquely identified as a leader. All hard disks almost equal quality. Companies that have faced serious problems have long since emerged from the market, while the rest give priority to reliability.
3.2 DVD Media
Conclusion
Bibliography
magnetic hard magnetic carrier
Introduction
The released data storage devices are a gamut of storage devices with different operating principles with physical and technical performance characteristics. The main property and purpose of data storage devices is its storage and playback.
All this effectively eliminates the issue of choosing a brand from the agenda. Of course, each vendor does not have models or product families, but you still have the Internet at hand to refer to the right forums. As a rule, stories about problematic models are always on top. Just keep in mind that information ages very quickly, as the production program is updated twice a year, and the product range is constantly being refined. It will be cheaper, and productivity will increase, but the question of how this modernization will affect reliability remains open.
Storage devices are divided into types and categories in connection with their operation principles, operational-technical, physical, software and other characteristics. For example, according to the principles of operation, the following types of devices are distinguished: electronic, magnetic, optical and mixed - magneto-optical.
Externally, products can look the same as twins, but they have a completely different implementation of the component. Damage to disks usually begins massively after they are taken out of production or disappear from the market. They are replaced by new developments with attractive specifications, but little is known about the internal driver and reliability. It is impossible to make technically sound conclusions about the weaknesses of "newcomers". From our point of view, we should not buy a new hard drive model that just appeared on the market.
Unsurpassed solutions are found in new models, and the quality in the first batch is still unstable, and you may face a manufacturing fault. Problems with firmware are also much more common in new models than in older ones. But nothing can be done on these issues - mass production in the market with high competition without defects can not.
Each type of device is organized on the basis of an appropriate technology for storing the playback / recording of digital information. Therefore, in connection with the type and technical performance of the information carrier, there are distinguished: electronic, disk and tape devices.
Magnetic disks are used as memory devices that allow storing information for a long time, with the power turned off. To work with magnetic disks, a device called a magnetic disk drive (HDD) is used. The main types of drives: drives on floppy disks (floppy disks); Hard disk drives (HDD); tape drives (NML); CD-ROM, CD-RW, DVD.
That's why our advice is to look for models that were at least six months ago - technology absorption has ended in this time, stagnation statistics are accumulating, and prices are falling. Under the same trademark, production lines with various uses are being launched, referring to different price categories and therefore having different performance and reliability. First, the consumer and corporate segments are divided. It can not be expected from desktop desktop reliability as a server.
They correspond to the main types of media: flexible magnetic disks (Floppy Disk); hard magnetic disks (Hard Disk); cassettes for streamers and other NML; CD-ROM, CD-R, CD-RW, DVD.
1. Magnetic storage
Magnetic drives are the most important medium for storing information in a computer and are divided into tape drives (NML) and magnetic disk storage (HDD).
Enterprise-class disks are assembled from high-quality components, thoroughly tested, with a more complex design and sophisticated firmware. Often the density of the recording is deliberately reduced. Their only drawback is a high price - two to two times more than the same capacity.
Burning and noise are very important for mass disks used in households. It is no coincidence that the so-called "green" models of 3, 5-inch disks are very popular. As a result, the discs shine less and show good reliability, but their performance is low.
Usually, magnetic recording uses impulse signals. Bit information is converted to alternating current in accordance with the alternation of zeros and ones.
This current flows to the magnetic head and, depending on the direction of the current in the head winding, a corresponding magnetic flux is formed in the space between the head and the carrier, which closes through the elementary region of magnetization (domain). The intrinsic magnetic fields of the domains are oriented in accordance with the direction of the external magnetic field. When the external field is removed, this state of domains does not change (long-term storage memory).
For deployment operating system for applications for a database with random access, a high-performance disk is required. But these discs are very hot and, as a rule, they need active cooling. Otherwise, the disc may be defective due to overheating.
The more, the better, the more often it is considered that the hard drive and the board never get. However, very often ignored the fact that reliability is inversely proportional to the volume of the hard disk. In the end, the larger the volume, the more magnetic plates and heads are used in the design, and therefore the probability of getting out of the head is higher. In addition, multi-discs consume more energy and shine, and the larger thickness of the package gives an increased load on the axis and predisposes to the spindle spindle even with a non-rigid stroke.
The main criterion for estimating storage devices on magnetic media is the surface recording density. It is defined as the product of the linear recording density along the track, expressed in bits per inch, and the number of tracks per inch. As a result, the surface recording density is expressed in megabits (Mbit / in2) or gigabit (Gb / in2) per square inch.
This, by the way, is one of the most complex failures in the practice of data recovery. Thus, large drives are much more capricious. They do not even like minor mechanical influences, they are also sensitive to overheating. Therefore, we advise you to treat such disks as fragile glasses - they need to be handled very carefully, even if they do not work. Care should also be taken when using the antistatic bags to which the products are supplied. As a result, a week later, half of them were no longer used for the reason why we could hardly imagine it.
In modern 3.5-inch drives, the value of this parameter is 10-20 Gb / in, and in experimental models it reaches 40 Gb / in. This allows you to produce storage capacity of more than 400 GB.
1.1. Drives on magnetic disks (NMD)
In NMD, a similar NML is provided for the possibility of sequential access to information. A magnetic disk storage device combines several serial access devices, and the reduction in the data retrieval time is ensured by the independence of access to the record from its location relative to other records.
For reference, this is about 400 times less than the human hair. So, let's briefly summarize. For reasons of reliability, all disks must be separated by the number of plates. To install the operating system, single-disk drives are the most suitable for storing data with two plates. Large disks with three or more plates are designed for less important information that does not require reserve copy. This can be media files, including downloading from the Internet. As for the purchase, everything seems clear, but we will repeat: do not buy a drive by hand or dusty shelves of small and questionable garage stores that attract you at a low price.
Technology NMD. In NMD as a data carrier, a package of metal disks (or payers) fixed to a rod around which they rotate at a constant speed is used. The surface of a magnetic disk covered with a ferromagnetic layer is called a working one.
The number of magnetic heads is equal to the number of working surfaces on one package of disks. If the package consists of 11 disks, the access mechanism consists of 10 holders with two magnetic heads on each of them. Holders of magnetic heads are united in a single unit in such a way as to ensure their synchronous movement along all the cylinders. The totality of the tracks achieved with a fixed position of the head block is called a cylinder. The distance between the cylinders (tracks) is called the feed, or the pitch of the track. The process of controlling the recording density is called precompensation. To compensate for the different recording densities, the Zone Bit Recording method is used, where the whole disk space is divided into zones (eight or more), each of which usually contains 20 to 30 cylinders with the same number of sectors.
But mechanical wear can not be "reset". Do not rely on warranty terms that are more illusive in such places. Small savings can lead to big problems, and who needs it? It becomes even more fun if the disc is seriously damaged, and the owner wants to quickly get rid of it, because the damage has not yet fully manifested itself.
Of course, if you know the seller for a long time, he is unlikely to use such tricks. Nevertheless, it is best to buy CDs from serious commercial companies that have long been on the market and provide a real guarantee for the entire production period. From time to time, a commercial company publishes statistical data in the warranty service center for returned discs. Some people treat him with excessive seriousness and plan their purchases exclusively in accordance with the ratings of some models of such data.
In the zone located on the outer radius (the lowest zone), a greater number of sectors (blocks) are recorded per track (120-96). To the center of the disk, the number of sectors decreases and in the oldest region reaches 64-56. Since the disk rotation speed is a constant value, more information comes from external zones with one disk revolution than from internal zones. This unevenness of information is offset by an increase in the speed of the data reading / conversion channel and the use of special tunable filters for frequency correction by zones. At the same time, the capacity of hard drives can be increased by approximately 30%.
What can we say to you - do not worry. In such cases, you need to remember three simple things. Many models with congenital structural defects - have peak problems after a certain period of time, and if the disk is released very soon, it may not yet have any known defects. For retail customers, any such statistics can be nothing more than entertainment. We do not know the criteria by which these statistics are compiled. . The choice between several defective models, starting with 1, 5-4%, makes sense only when purchasing whole batches of thousands of units.
1.2 Hard disk drives
Design and operation of the device. In the HDD, several plates (disks) or platters are installed inside the drive. The plates have a diameter of 5.25 or 3.5 inches. In new developments, glass is being tried, because it has more resistance and will make discs thinner than aluminum counterparts.
When buying a device, the probability of failure in this situation is 50% - it can be damaged or can not be damaged. The only thing that makes statistical reports useful is to clarify the quality trends. Rule of gold reliability: if you need more volume, you will have to compromise the high speed of the spindle.
There are no perfect and completely reliable disks, so everyone can get damaged. As they say at seminars, hard drives are unreliable. On the other hand, they have a warranty card. All we can do is choose the drive according to our needs and operate it correctly. Of course, we must not forget about backing up important data - regardless of the complexity of the backup, recovery will be much cheaper.
Characteristics of HDD. The characteristics of the hard disk are very important for assessing the performance of the system as a whole. The effective speed of the hard drive depends on a number of factors.
The decisive among them is the disk rotation speed, which is measured in rpm (rpm) and directly affects the data transfer rate in the HDD. While the fastest HDDs with EIDE interface had a speed of about 5400 rpm, the SCSI-HDD can accelerate to 7200 rpm. The average disk access time is the interval between the time the data is requested and the time it is accessed (measured in milliseconds (ms)). The access time includes the actual search time, the waiting time, and the processing time.
But if you still need data recovery, contact a specialist. Artisans, such as "system administrators for everything," will not help you in this and in many other cases, because they are "large-format" computer engineers. The amateur, armed with a screwdriver, exchanges the "sick" PCB with electronics from a hard double disk, then gets two "corpses".
Therefore, we assume that you have chosen a new 3, 5-inch drive for your system, put it in the right place, properly installed and connected to quality cables. There is a period of operation. To be as long as possible, and you do not have problems, you must provide a disk with the most convenient working conditions. Each disk needs good power, good cooling and mechanical protection. There is no need to periodically check the status of the disk.
Search time - the total time required to search the read / write head for the physical location of data on the disk. The latency is the average time to access the sector during the rotation process. It is easily calculated from the rotational speed of the drive axis as a half-turn time.
The transfer speed of the disk (sometimes called media-speed) is the speed at which data is transferred to the drive and read from it. It depends on the recording frequency and is usually measured in megabytes per second (MBps, MB / s).
Quality of power supply. . It is completely determined by the power supply of the computer. There are also some relations and contacts of the power connectors, on which a certain voltage drop can be observed. The power supply must be a trusted brand and have sufficient power, and the power supply network must be grounded.
Choosing the right food source is an important and important topic that we are constantly addressing. Nevertheless, we must admit that in recent years even budget models have been improved, and hard drives have been able to adapt to them. The situation develops to two levels. Ugly models disappeared from the market and retreated to other brands that use more basic hardware and schematics. There are no similar problems in the middle and high class. Each power supply unit can properly "feed" the disks until a suitable power sample is selected, and all loads on the different lines are correctly distributed.
Data transfer rate (or DTR - Data Transfer Rate) is the speed at which a computer can transmit data via buses (usually IDE / EIDE or SCSI) to the CPU. Some data providers indicate the internal transfer rate, data transfer from the head to the built-in disk buffer. Others lead the data packet transfer rate, the maximum transmission rate for ideal parameters or for a short duration. The speed of external data transmission is more important.
2. Types of magnetic carriers
2.1 Flexible magnetic disks
The diskette consists of a round polymer substrate, covered on both sides with magnetic oxide and placed in a plastic package, on the inner surface of which is applied a cleaning coating. In the packaging on both sides, radial slots are made through which the read / write heads of the drive get access to the disk.
Diskettes of each type are usually two-sided. The single track density is 48 tpi (lanes per inch), double is 96 tpi and high is usually 135 tpi.
When a 3.5 "disc is inserted into the device, the protective metal shutter moves away, the drive spindle enters the middle hole, and the side pin of the drive is placed in a rectangular positioning hole located side by side. The motor rotates the disc at a speed of 300 rpm.
Floppy disk drives use the so-called "open loop tracking", they do not actually look for a track, they just set the head to the "correct" position. In hard disks, on the other hand, servo motors use heads to check positioning, which makes it possible to record with a transverse density many hundreds of times higher than is possible on a floppy disk.
The head is moved by the lead screw, which in turn is controlled by the stepping motor, and when the screw is turned to a certain angle, the head passes the set distance. The density of writing data to a floppy disk is limited by the accuracy of the stepper motor, in particular, this means 135 tpi for floppy disks 1.44 MB. The disk has four sensors: a disk motor; write protection; the presence of a disk; and track sensor 00.
2.2 External hard drives on the HDD
In recent years, technologies for placing standard HDDs in a mobile (portable) external case (box) that has been connected to the computer via an external interface have spread.
Since today the capacity of the HDD is measured in gigabytes, and the sizes of multimedia and graphic files are tens of megabytes, the capacity from 100 to 150 MB is sufficient to make the media occupy the traditional niche of the floppy disk - moving several files between users, archiving or backing up individual files or directories and sending files by mail. In this range, a number of devices are proposed for the next generation of floppy disks that use flexible magnetic media and traditional magnetic storage technology.
Zip drives. Without a doubt, the most popular device in this category is the Zip Iomega drive, first released in 1995. The high efficiency of Zip drives is provided, firstly, by a high rotation speed (3000 rpm), and secondly by the technology offered by Iomega (which is based on the aerodynamic effect of Bernoulli), while the floppy disk "sucks" to the read / write head, and not vice versa, as in the HDD. Zip disks are soft, like flexible disks, which makes them cheap and less susceptible to shock loads.
Zip-drives have a capacity of 94 MB and are available in both built-in and external versions. The internal modules correspond to the 3.5-inch form factor, use the SCSI or ATARI interface, the average search time is 29 ms, and the transfer rate is 1.4 KB / s.
Superdiscites. The range from 200 to 300 MB is best matched by the concept of a territory of superdiscade. The capacity of such devices is 2 times higher than that of an alternate floppy disk drive, and is more characteristic for HDD than for a floppy disk. Devices in this group use magnetic or magneto-optical technology.
In 2001, Matsushita announces the FD32MB technology, which gives an option for high-density formatting of a conventional HF floppy disk at 1.44 MB to provide storage capacity of up to 32 MB on disk. The technology consists in increasing the recording density of each track on a HD floppy disk using a superdisk magnetic reading head and a conventional magnetic head for data recording. While 80 circular data tracks are placed on a conventional floppy disk, in FD32MB this number is increased to 777. At the same time, the 187.5 micron track for the HD disk is reduced to about 18.8 microns.
Replaceable Hard Drives. The next capacity interval (from 500 MB to 1 GB) is sufficient to backup or archive a disk partition (partition) of a reasonably large size.
In the range of more than 1 GB, removable disk technology is borrowed from conventional HDDs. Released in mid-1996 drive Iomega Jaz (replacement hard drive for 1 GB) was perceived as an innovative product. When Jaz appeared on the market, it immediately became clear where to use it - users could create audio and video presentations and transfer between computers. In addition, such presentations could be launched directly from the Jaz media, without having to rewrite the data on the HDD.
Flash Memory. Not referring to magnetic media, flash memory works simultaneously like RAM and HDD. It reminds ordinary memory in the form of discrete chips, modules, or memory cards, where, just as in DRAM and SRAM, data bits are stored in memory cells. However, just like the HDD, the flash memory is nonvolatile and saves data even when the power is off.
Technology ETOX is the dominant flash-technology, which occupies about 70% of the entire market of nonvolatile memory. The data is entered into flash memory bit by bit, by byte or by words using an operation called programming.
Although electronic flash drives are small, fast, use little energy and are capable of withstanding impacts up to 2000g without destroying the data, their limited capacity makes them an inappropriate alternative to the PC hard drive.
3. Optical technologies
3.1 CDs
Initially, CDs were used exclusively in high-quality sound reproducing equipment, replacing obsolete vinyl records and tape cassettes. However, soon laser discs were also used on personal computers. Computer laser discs were called CD-ROM. In the late 90's. the device for work with CD-ROM became a standard component of any personal computer, and the vast majority of programs began to be distributed on CDs.
The drive is on a CD-ROM (CD-ROM). The reading of information from the CD-ROM occurs with the help of a laser beam of lower power. The servomotor, upon command from the internal microprocessor of the drive, moves the reflecting mirror or prism. This allows you to focus the laser beam on a specific track. The laser emits coherent light, consisting of synchronized waves of equal length. The beam, reaching the light reflecting surface (pad), through the splitting prism, is deflected to the photodetector, which interprets this as "1", and falling into the depression (pit) is dissipated and absorbed - the photodetector fixes "0".
While the magnetic disks rotate at a constant number of revolutions per minute, i.e. with a constant angular velocity, the CD rotates usually at a variable angular velocity to ensure a constant linear speed during reading. Thus, reading internal tracks is carried out with increased, and external - with a reduced number of revolutions. This is the reason for the lower speed of data access for CDs compared to hard disks.
3.2 DVD Media
A versatile digital versatile disc (DVD) is a kind of drive that, unlike CD, since its introduction into the market has been designed for wide application in both audio-video and computer industry. DVDs, having the same size as a standard CD (120 mm in diameter, 1.2 mm thick), provide up to 17 GB of memory with a transfer speed higher than for a CD-ROM, have access time similar to a CD-ROM, and are divided into four versions:
DVD-5 - single-sided single-layer disc, with a capacity of 4.7 GB;
DVD-9 - a one-sided two-layer disc of 8.5 GB;
DVD-10 - two-sided single-layer disc 9.4 GB;
DVD-18 - capacity up to 17 GB on a two-sided double-layer disc.
DVD-ROM. As for the disc itself, there is little difference between DVD and CD-ROM drives, since the only obvious is the DVD logo on the front panel. The main difference is that the CD-ROM data is written close to the top layer of the disk surface, and the data level for the DVD is closer to the middle so that the disc can be two-sided. Therefore, the optical drive reader of a DVD-ROM drive is more complex than its analog for a CD-ROM, in order to create the ability to read both one and the other of these types of media.
One of the earliest solutions was to use a pair of rotary lenses: one for focusing the beam on DVD data levels and the other for reading conventional CDs. Subsequently, more sophisticated designs have emerged that eliminate the need to switch the lens. For example, the "double discrete optical sample" proposed by Sony has separate lasers optimized for CD (wavelength 780 nm) and DVD (650 nm). Panasonic devices switch laser beams using a holographic optical element capable of focusing the beam at two different discrete points.
DVD-ROM drives rotate the disc much slower than their CD-ROM counterparts. However, since DVD data is packed much more densely, its performance is significantly higher than that of a CD-ROM at the same speed. While a normal CD-ROM audio CD (lx or single) has a maximum transfer rate of 150 KB / s, a DVD (1x) drive can transmit data at 1250 KB / s, which is achieved only with an eight-fold (8X) CD- ROM.
There is no generally accepted terminology for describing the various "generations" of DVD drives. However, the term "second generation" (or DVD II) usually refers to 2 high-speed drives that are also capable of reading CD-R / CD-RW media, and the term "third generation" (or DVD III) usually means 5-speed drives (or sometimes 4.8x, or 6x), some of which are capable of reading DVD-RAM media.
Recordable DVD Formats
There are several versions of recordable DVDs:
DVD-R conventional, or DVD-R;
DVD-RAM (rewritable);
Recordable DVD. The DVD-R (or recordable DVD) is in many respects conceptually similar to the CD-R - it is a write-once media that can contain any type of information normally stored on a DVD of mass production - video, audio, pictures, data files, programs, multimedia and so on. etc. Depending on the type of information being recorded, DVD-R discs can be used on virtually any compatible DVD playback device, including DVD-ROM drives and DVD video players. Since the DVD format supports two-sided discs, up to 9.4 GB can be stored on a two-sided DVD-R disc. Data can be written on DVD with a speed of 1x (11.08 Mbit / s, which is approximately equivalent to the speed of 9x CD-ROM). After recording, DVD-R discs can be read at the same speeds as massively reproduced discs, depending on the "x-factor" (speed ratio) of the DVD-ROM drive used.
DVD-R, like CD-R, uses a constant linear velocity (CLV) to maximize the recording density on the disk surface. This requires a change in RPM (rpm), as the diameter of the track changes as you move from one edge of the disk to the other. Recording starts on the inside and ends on the outside. At a speed of 1x, the rotation speed varies from 1623 to 632 rpm for a 3.95 GB disk and from 1475 to 575 rpm for 4.7 GB depending on the position of the recording / reproducing head on the surface. For a 3.95 GB disk, the interval (feed) of tracks, or the distance from the center of one turn of the spiral track to the adjacent part of the track, is 0.8 μm (micron), which is half that of the CD-R. On a 4.7 GB disk, an even smaller track feed of 0.74 μm is used.
DVD-RAM.The rewritable DVD-ROM or DVD-RAM uses phase-shift technology that is not purely optical CD and DVD technology, but a combination of some features of magneto-optical methods and its origin from optical disk systems. The applied "land groove" format allows you to record signals both on depressions formed on the disk and in the gaps between grooves. Depressions and sector headers are formed on the surface of the disk during its casting.
In mid-1998, the first generation of products for reusing DVD-RAM with a capacity of 2.6 GB on both sides of the disk appeared. However, these early devices are incompatible with higher-capacity standards that use the contrast expansion layer and the thermal buffer layer to achieve a higher recording density. The specification for version 2.0 of DVD-RAM with a capacity of 4.7 GB on one side was released in October 1999.
DVD-RW.Known earlier as DVD-R / W or DVD-ER, the DVD-RW media (which became available in late 1999) appears in the evolutionary evolution of the existing CD-RW / DVD-R technologies by Pioneer.
DVD-RW discs use technology to change the phase state of a substance for reading, writing and erasing information. A laser beam with a wavelength of 650 nm heats the sensitive alloy layer to transfer it to either the crystalline (reflecting) state or the amorphous (dark, non-reflective), depending on the temperature level and the subsequent cooling rate. The resulting difference between the recorded dark marks and erased reflections is recognized by the player or the disc drive and allows to reproduce the stored information.
The DVD-RW media uses the same physical addressing scheme as the DVD-R. During recording, the laser of the drive follows the microscopic indentation, recording data in a spiral path.
One of the main advantages of the third rewritable DVD format - DVD + RW - is that it provides better compatibility than any of its competitors.
DVD + RW.The DVD-RAM specification was a compromise between two different offers of the main competitors - Hitachi, Matsushita Electric and Toshiba, on the one hand, and the Sony / Philips alliance on the other.
DVD + RW has much in common with competing DVD-RW technology, because it uses a medium with a phase state change, and assumes a user experience obtained using CD-RWs. In DVD + RW format, discs can be recorded in both constant line speed (CLV) mode for sequential video recording and in constant angular velocity (CAV) format for direct access.
DVD + R. The two-layer system DVD + R uses two thin organic films of the material to be painted, separated by a spacer (filler). Heating by a concentrated laser beam irreversibly changes the physical and chemical structure of each layer so that the changed regions receive optical properties different from the initial ones. This leads to fluctuations in the reflectivity when the disc rotates and creates a read signal the same as in the stamped DVD-ROMs.
Conclusion
Thus, we can draw the following general conclusions:
Magnetic drives are the most important medium for storing information in a computer and are divided into tape drives (NML) and magnetic disk storage (HDD).
Magnetic disks are used as memory devices that allow storing information for a long time, with the power turned off.
The main types of drives: drives on floppy disks (floppy disks); Hard disk drives (HDD); tape drives (NML); CD-ROM, CD-RW, DVD.
The main types of media: flexible magnetic disks (Floppy Disk); hard disk drives (Hard Disk); cassettes for streamers and other NML; CD-ROM, CD-R, CD-RW, DVD.
There are several versions of recordable DVDs: DVD-R conventional, or DVD-R; DVD-RAM (rewritable); DVD-RW; DVD + RW.
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Introduction
The goal that the author poses in writing this article is to help the user navigate the current market for hard disks to personal computers. At the moment, the choice of hard drive is quite difficult, as some traditional manufacturers of this product have changed the nature of their activities.
First of all, it is necessary to note the merger of two giants of this market segment - Quantum and Maxtor. Now widely known and popular hard drives with the name Quantum will no longer be. This manufacturer will deal with data storage systems for large systems. However, Quantum's production facilities will not be abandoned. All the best practices of the company will find their application in hard disks with the Maxtor brand. By the way, it is this company that will assume all the warranty responsibility for previously sold Quantum hard disks. And also Maxtor will use the dealer network of its partner to promote its products. This is especially true for Russia, where Maxtor until recently was very poorly represented.
Fujitsu decided to leave the hard disk market for desktop computers. What caused this decision, it is difficult to say at the moment. Representatives of the company comment on this step by the fact that the global financial crisis in the field of electronics hit the company's budget and "the weakest sheep must be stabbed". On the other hand, Fujitsu's latest hard drives were very high-end, and it's just that the language does not turn to be called noncompetitive. Not only out of respect for this, we decided to include hard drives of this manufacturer in this review.
The model considered by us is very well sold now in the Russian market of computer hardware.
In this review we will consider:
- Western Digital Caviar WD1000BB
- IBM Deskstar 60GXP
All of them have a spindle rotation speed of 7200 rpm (excluding the Maxtor 536DX). Which by today's standards has become the norm. Let's pass to our first researched hard disk.
Seagate likes to give its solutions unique emblems. The logo of this hard disk is recognized right away.
- 7200 spindle revolutions per minute
- 60GB, models up to 80GB are also available
- 40GB per plate (20GB on each side)
- 2MB Cache Buffer
- 8.9 ms average access time
- Ultra ATA / 100 IDE interface
- SoftSonic Fluid Bearing Motor
Traditionally on one side of the disk there is information about the characteristics of the device, and on other information about the operating conditions and the adjustment of the connection of the hard drive.
Seagate Barracuda ATA IV has a significant minus. Winchester is very hot. The developers of the hard drive, fighting the noise, lost in the heat sink. Indeed, the noise level is only 2.4 dB, and achieved this with a special motor and gasket in the body. It is the obstacle for a good heat sink ( strongly resembles a conventional password :) the editor). In the picture you see its porous structure:
Otherwise, this is a very interesting solution, which, no doubt, will decorate any system unit. The test data will be given in a separate chapter.
This is one of the latest models of hard drives for desktop companies from this manufacturer. As I said above, Fujitsu refused to continue working in this segment of the market.
The hard drive itself has the following characteristics (declared by the manufacturer):
- Ultra ATA / 100 interface (allowing up to 100 MB / s bus transfer)
- Heads of the sixth generation Giant Magneto-Resistive (GMR)
- Density on the plate up to 20.4GB
- The recording density is 16.2 GB / in2
- Access speed 8.5ms
- The average data transfer rate is 60.7 MB / s
- Buffer cache 2MB
This is how this hard disk looks from both sides:
On the back cover there is information about installing the hard disk in the computer. However, there is no warranty information and no operating conditions. This approach of the manufacturer is absolutely not happy. The following picture shows the jams and physical characteristics of the hard disk:
Fujitsu MPG3204AH-E is a good workhorse for home computer. However, the size of this hard drive to date can not satisfy most users. This disk can become a good competitor to the HDDs presented in this section only in the field of office personal computers.
From the minuses I want to note the high temperature of this hard drive. So its owners should take care of the good cooling of their system unit. Otherwise, overheating can cause data loss.
Maxtor is not well known to Russian users, or better to say - less familiar than others. In the West, hard drives of this company have long and firmly established themselves in system units personal computers.
Maxtor positions its solutions on the widest range of users. Its new model Maxtor 536DX is intended, first of all, for users who actively use their computers to host databases on them. However, in all situations, when you need volume to store large data, the Maxtor 536DX model can be a great help in this. The price of this hard drive varies in the range of 230-260 dollars.
The hard drive itself has the following characteristics (declared by the manufacturer):
