-According to the U.S. Environmental Protection Agency, nearly 250 million computers will become obsolete in the next five years. Unfortunately, less than 20 percent of PCs retired in the U.S. are recycled most years, instead creating what is being termed "e-waste."
To help reverse this trend, the U.S. government recently passed legislation that imposes penalties and fines on companies that do not practice environmentally proper IT disposal. According to a survey conducted by HP, the majority of companies-especially small-to-medium businesses (SMBs)-underestimate the security, financial and environmental impact of technology equipment disposal. Key findings include:
• 70 percent of respondents underestimate the cost of disposing of PCs;
• 66 percent of executives with purchasing authority are unaware of the financial implications of ignoring environmental regulations when disposing of IT equipment; and
• The biggest concern regarding disposal of IT equipment is data security and privacy.
So, what is the "politically correct" way to dispose of aging technology equipment? IT leaders like HP are increasing their commitment to real-world solutions that help customers achieve environmental responsibility, while also helping them get a better return on their IT investments.
E-Cycling computers and their components can be done to build new computers. HP helped its customers recycle more than 140 million pounds of hardware and print cartridges last year-the equivalent weight of 280 jumbo airliners! More and more retailers are also offering recycled products, which helps keep them out of landfills and other disposal sites.
Leasing is another way for companies to mitigate the various risks involved with acquiring IT assets, because the lessor assumes the responsibility for proper disposal of equipment at the end of its useful life. Leasing protects customers against the fines and consequences associated with violating environmental regulations, as well as from violations of data security and personal privacy laws. Similarly, older systems can be traded in for discounts on the price of new machines through such programs as HP's "Ditch Your Dinosaur," which offers a $100 rebate when customers trade in an outdated computer.
Donating computers to charities in need is a positive option to consider. Like older cars, they can be used as an effective tax write-off for a business, while benefiting worthwhile organizations. For example, HP and many others work with the National Cristina Foundation. This organization helps people with disabilities, students at risk and economically disadvantaged persons lead more independent and productive lives by providing them with computer technology and training.
Showing posts with label Hardware. Show all posts
Showing posts with label Hardware. Show all posts
Labels:
Hardware
Guide to Buying a Laptop Computer
With the many different brands and models on the market, buying a laptop or notebook computer may at first seem confusing. But simply breaking down the process into a few key areas and using Myshopping.com.au to search for the most suitable features and pricing makes it much easier to access exactly the machine you're looking for.
How important to you is mobility?
Mobility in laptop computers is a combination of size, weight and battery life: how often you carry it around, and if you will be relying mainly on the notebook's battery, or whether you will access an external power source. Laptops can weigh from a little over 1 kg up to 6kg, depending on the model and features included. The screen, storage space and disc drive all affect the weight.
Battery life is shortened by bigger screens and multiple disc drives. Manufacturers advertise the weight of the laptop in their specifications, but it is important to consider whether that specification includes batteries and other peripherals such as external drives that you may be lugging around. The most common battery type is Lithium Ion (Li-Ion), which can operate for one to three hours under normal working conditions. But many power saving options available and higher celled batteries can extend the discharge time considerably. Battery life deteriorates over time however, and as your laptop ages; the discharge rate of the battery will diminish. Sometimes it is worthwhile carrying an additional battery.
Application and cost
If mobility is of a lesser concern, then battery life and weight will be less important. You may be more inclined to have a bigger processor, screen size and memory capacity. The type of work you do can affect the screen size and type that is most suitable for you. For a lighter load, and less graphics intensive applications a 12-14in screen instead of 15 or 17in widescreen will be more suitable. If, on the other hand, the graphics capabilities and size of the screen are important then the best screen you can afford will be more of a priority. It may work out cheaper to buy a basic unit and add such things as an external TV card and DVD burner when the need arises.
How much you need to spend is closely related to how you use your laptop. If you only want to access your e-mail, browse the Web and do word processing, then you can consider lower budget machines with smaller processors, screens and facilities.
A medium-level user, perhaps playing games or working in multimedia applications, will need a powerful processor, graphics controller, storage space, and a bigger screen. The more features your laptop has, the more expensive it will be. Including a DVD-burner instead of DVD-ROM, hard drive capacity of more than 40GB, a 17in widescreen screen and wireless capabilities results in a more expensive machine.
If you are not looking for high power and graphics capabilities, then you may find a suitable laptop for around $1500. The latest processor, full blown graphics capability, DVD burner, widescreen and wireless connectivity may cost over $4000. Use Myshopping.com.au to search with different price ranges.
Other key components
Having determined by what you will do with it, and how mobile you need to be that you are definitely buying a laptop, you now need to get down to the nitty gritty and find the specifications that will meet your needs. So, what to look for? Essentially, you are considering differences between the following components: display, graphics controller, memory (RAM), hard disk, removable storage, networking options, peripheral connectivity, sound and battery.
Display and Graphics
Notebooks now all feature LCD screens (Liquid Crystal Displays) presenting crisp text and reduced eyestrain. These screens display sharper text than standard CRT monitors, but are less capable of displaying well-rendered graphics. If you will be using your notebook for graphics work, it may be worthwhile having a CRT monitor to connect to. Screen sizes for notebooks range from 12.1in to 17in (widescreen). A 15in display or 15.4in widescreen alternative is the most common in notebooks today. Widescreen is quickly becoming more common, partly to accommodate playback of DVDs and also because widescreen proportions make it is more durable.
On-screen graphics are affected by both the size and type of screen as well as the graphics card. It is reasonably safe to assume that larger displays offer higher on-screen resolution. Screen brightness (measured in nits) is another specification that can vary between makes and models. Brighter screens impact less on eyes and can be more easily read in bright conditions. Some manufacturers have a glossy, reflective coating over the display improving contrast and colours. But, because it increases the reflectivity of the screen, it can show you reflected in the screen. Surface scratches may also show up more readily. Not all LCD screens have the same viewable angle, with some screens not easily viewed from a side angle.
Graphics performance in laptops is still inferior to that of desktop machines. All graphic controllers easily render 2-D images and if you don't need more from your graphics, then an integrated graphics controller is ample. However, if you want to play the latest 3-D games at a decent resolution and frame rate or you're a CAD designer, then you'll need a discreet graphics controller with a dedicated DDR video memory.
Memory and Storage
In all computers RAM chips keep the CPU efficiently fed with data or instructions from programs on the hard drive. Notebook computers now commonly use DDR SDRAM (Double Date Rate SDRAM), the default standard, and DDR2 SDRAM which is a next-generation memory type offering considerable performance and power benefits over SDRAM. Either way, when it comes to RAM, more memory is better and you should consider 256MB as the absolute minimum. Upgrading memory can achieve better performance, and quite a number of vendors offer higher RAM configurations as a 'deal sweetener' at the time of purchase. Search through Myshopping.com.au for bundled extras such as more RAM.
The hard drive provides the long-term storage and is the centre of program control. There are two critical specifications of hard disks. One is disk speed, measured in revolutions per minute (rpm). Faster disks speeds provide quicker access for loading and saving and 'file swapping'. The other is storage capacity, and drives are now available for notebook computers with 120GB capacity. If you work with large file sizes, then you will probably want at least 40GB of hard drive space. You may also want to consider the type of removable storage such as a DVD writer, removable hard disks and media or 'flash' card systems that will suit your use best.
Networking and connectivity
Laptop computers now include 56Kbps modem (RJ-11) and 10/100 Ethernet (RJ-45) connections as standard features. Some feature an Infrared port and you can use it to connect your mobile phone. Other wireless technology for connecting mobile phones, printers and PDA devices includes Bluetooth and Wi-Fi, allowing connection at certified public access points and home wireless networking. Most laptops use USB 2.0 or FireWire connection for connecting keyboard, mouse, printers, cameras and other peripherals. Nearly every new notebook will have around three USB 2.0 ports, and one FireWire port and a VGA-out port to connect an external monitor to.
Notebook computers have traditionally been able to expand their capability through simple plug-in PC Cards. Recently a new standard has emerged called ExpressCard, a smaller, faster and more portable plug-in card to provide such things as expanded video and sound capacity.
Choosing a laptop becomes much easier once you've decided on these basic requirements. You can search Myshopping.com.au to compare makes, models, prices, accessories and all the important specifications. You can also compare vendors and their prices and service
How important to you is mobility?
Mobility in laptop computers is a combination of size, weight and battery life: how often you carry it around, and if you will be relying mainly on the notebook's battery, or whether you will access an external power source. Laptops can weigh from a little over 1 kg up to 6kg, depending on the model and features included. The screen, storage space and disc drive all affect the weight.
Battery life is shortened by bigger screens and multiple disc drives. Manufacturers advertise the weight of the laptop in their specifications, but it is important to consider whether that specification includes batteries and other peripherals such as external drives that you may be lugging around. The most common battery type is Lithium Ion (Li-Ion), which can operate for one to three hours under normal working conditions. But many power saving options available and higher celled batteries can extend the discharge time considerably. Battery life deteriorates over time however, and as your laptop ages; the discharge rate of the battery will diminish. Sometimes it is worthwhile carrying an additional battery.
Application and cost
If mobility is of a lesser concern, then battery life and weight will be less important. You may be more inclined to have a bigger processor, screen size and memory capacity. The type of work you do can affect the screen size and type that is most suitable for you. For a lighter load, and less graphics intensive applications a 12-14in screen instead of 15 or 17in widescreen will be more suitable. If, on the other hand, the graphics capabilities and size of the screen are important then the best screen you can afford will be more of a priority. It may work out cheaper to buy a basic unit and add such things as an external TV card and DVD burner when the need arises.
How much you need to spend is closely related to how you use your laptop. If you only want to access your e-mail, browse the Web and do word processing, then you can consider lower budget machines with smaller processors, screens and facilities.
A medium-level user, perhaps playing games or working in multimedia applications, will need a powerful processor, graphics controller, storage space, and a bigger screen. The more features your laptop has, the more expensive it will be. Including a DVD-burner instead of DVD-ROM, hard drive capacity of more than 40GB, a 17in widescreen screen and wireless capabilities results in a more expensive machine.
If you are not looking for high power and graphics capabilities, then you may find a suitable laptop for around $1500. The latest processor, full blown graphics capability, DVD burner, widescreen and wireless connectivity may cost over $4000. Use Myshopping.com.au to search with different price ranges.
Other key components
Having determined by what you will do with it, and how mobile you need to be that you are definitely buying a laptop, you now need to get down to the nitty gritty and find the specifications that will meet your needs. So, what to look for? Essentially, you are considering differences between the following components: display, graphics controller, memory (RAM), hard disk, removable storage, networking options, peripheral connectivity, sound and battery.
Display and Graphics
Notebooks now all feature LCD screens (Liquid Crystal Displays) presenting crisp text and reduced eyestrain. These screens display sharper text than standard CRT monitors, but are less capable of displaying well-rendered graphics. If you will be using your notebook for graphics work, it may be worthwhile having a CRT monitor to connect to. Screen sizes for notebooks range from 12.1in to 17in (widescreen). A 15in display or 15.4in widescreen alternative is the most common in notebooks today. Widescreen is quickly becoming more common, partly to accommodate playback of DVDs and also because widescreen proportions make it is more durable.
On-screen graphics are affected by both the size and type of screen as well as the graphics card. It is reasonably safe to assume that larger displays offer higher on-screen resolution. Screen brightness (measured in nits) is another specification that can vary between makes and models. Brighter screens impact less on eyes and can be more easily read in bright conditions. Some manufacturers have a glossy, reflective coating over the display improving contrast and colours. But, because it increases the reflectivity of the screen, it can show you reflected in the screen. Surface scratches may also show up more readily. Not all LCD screens have the same viewable angle, with some screens not easily viewed from a side angle.
Graphics performance in laptops is still inferior to that of desktop machines. All graphic controllers easily render 2-D images and if you don't need more from your graphics, then an integrated graphics controller is ample. However, if you want to play the latest 3-D games at a decent resolution and frame rate or you're a CAD designer, then you'll need a discreet graphics controller with a dedicated DDR video memory.
Memory and Storage
In all computers RAM chips keep the CPU efficiently fed with data or instructions from programs on the hard drive. Notebook computers now commonly use DDR SDRAM (Double Date Rate SDRAM), the default standard, and DDR2 SDRAM which is a next-generation memory type offering considerable performance and power benefits over SDRAM. Either way, when it comes to RAM, more memory is better and you should consider 256MB as the absolute minimum. Upgrading memory can achieve better performance, and quite a number of vendors offer higher RAM configurations as a 'deal sweetener' at the time of purchase. Search through Myshopping.com.au for bundled extras such as more RAM.
The hard drive provides the long-term storage and is the centre of program control. There are two critical specifications of hard disks. One is disk speed, measured in revolutions per minute (rpm). Faster disks speeds provide quicker access for loading and saving and 'file swapping'. The other is storage capacity, and drives are now available for notebook computers with 120GB capacity. If you work with large file sizes, then you will probably want at least 40GB of hard drive space. You may also want to consider the type of removable storage such as a DVD writer, removable hard disks and media or 'flash' card systems that will suit your use best.
Networking and connectivity
Laptop computers now include 56Kbps modem (RJ-11) and 10/100 Ethernet (RJ-45) connections as standard features. Some feature an Infrared port and you can use it to connect your mobile phone. Other wireless technology for connecting mobile phones, printers and PDA devices includes Bluetooth and Wi-Fi, allowing connection at certified public access points and home wireless networking. Most laptops use USB 2.0 or FireWire connection for connecting keyboard, mouse, printers, cameras and other peripherals. Nearly every new notebook will have around three USB 2.0 ports, and one FireWire port and a VGA-out port to connect an external monitor to.
Notebook computers have traditionally been able to expand their capability through simple plug-in PC Cards. Recently a new standard has emerged called ExpressCard, a smaller, faster and more portable plug-in card to provide such things as expanded video and sound capacity.
Choosing a laptop becomes much easier once you've decided on these basic requirements. You can search Myshopping.com.au to compare makes, models, prices, accessories and all the important specifications. You can also compare vendors and their prices and service
Labels:
Hardware
Perpendicular Hard Disk Drive
What is a Hard Disk Drive?
A Hard Disk Drive (HDD) is a device used by modern computers to permanently store information. The Hard Disk Drive is arguable the most essential part of a computer system in that all the information that is permanently stored is contained within its enclosure, including your computer's Operating System (OS). Thanks to Hard Disk Drives, long gone are the days when you would have had to keep all your programs and documents stored on removable media such as Floppy Disks or CD-ROMs.
Originally invented in the mid 1950's and made commercially available in 1956 by International Business Machines (IBM). Called RAMAC (Random Access Method of Accounting and Control), the first Hard Disk Drives contained as much as 50 platters which were 24 inches in diameter and were computers in their own right albeit with a single purpose – to store data. The entire unit which housed the hard drive was the approximate size of two large refrigerators placed side by side. In the 50 or so years since their invention, Hard Disk Drives have steadily and aggressively far out paced Moore's law. Which stipulates that memory in computers will increase by 100% approximately every 18 months. Hard Disk Drives on the other hand have increased capacity in the same period by approximately 130%, an increase of 100% every nine months in many cases. Such capacity increases are being threatened, however.
In the years since the first Hard Disk Drive very little has changed apart from logical steps in technology such as the increased speed or improved interfaces, the basic technology has changed very little. There have been no technological leaps, as it were, for Hard Disk Drives beyond their increased miniaturisation. Apart from miniaturisation and recording media improvements the Hard Disk Drive as a device is almost identical technologically speaking, to the very first, the RAMAC.Hard Disk Drives use a similar technology as is employed in audio and video cassettes. Such audio and video cassettes use a magnetic ribbon wound around a two wheels to store data. To access a particular portion of the data contained on the magnetic ribbon, the device must wind the tape such that the beginning of the section containing the data is underneath the device that reads the data (the magnetic read/write head). This process is called sequential data retrieval because in the process of accessing the particular data, the device must sequentially read each piece of data until the data it's looking for is found. This process is very time consuming and contributes to wear.
Hard Disks on the other hand use a circular disk-shaped platter upon which the magnetically sensitive compound is laid. Such platters are similar in concept to a Compact Disk (CD) in that the data they hold can be accessed randomly, that the recordable media is in a circular (disk) shape, and that the data is sectioned off into tracks and sectors. Data on a Hard Disk Drive can be accessed randomly because the recordable medium of Hard Disk Drives uses these separated tracks and sectors. By separating the data in such a way, it can be positioned at random intervals of the disk, depending upon the space requirements.
Anywhere from one to seven recordable platters are contained within a modern Hard Disk Drive's metallic enclosure. Hard Disk Drive platters are perfectly circular disks made from either an aluminium alloy or a more recently a glass ceramic substrate which is a ceramic disk suspended in a glass outer shell. Onto the surfaces of a disk's platter is laid a thin layer of a magnetically sensitive coating called the recording medium, in modern drives the mixture is a complex amalgam of different materials such as cobalt chromium platinum boron (CoCrPtB) and other such rare metals.
How does a Hard Disk Drive store data?
All information located on a computer is expressed as a series of ones and zeros (1/0), as binary digits (bits). Taking advantage of the nature of magnetic particles, that they can be polarised to magnetic north or south and that their magnetic poles can be alternated or switched when a sufficient magnetic field of the correct polarity is applied, Hard Disk Drives can store the very same sequence of bits onto a disk by polarising the required magnetic particles on the recording medium such that they represent the data being stored. Hard Disk Drives are sectioned off such that they contain both intersecting tracks and sectors. The purpose of which is to provide a logical data structure, to provide a way to distinguish between areas of data. Within each track there are a number of sectors. It is within these sectors of the Hard Disk which data is stored.
The platter of a Hard Disk Drive is coated with a magnetically sensitive coating comprised primarily of magnetically charged particles or filings which as a whole may be called the recording medium. These particulates can be magnetically aligned such that they represent binary digits, by inducing an electromagnetic field upon them via a devices read/write head. The recording media contains many billions of microscopic particles which when viewed extremely close resemble miniature metal filings. When a Hard Disk Drive records data onto the medium it takes many hundreds (usually anywhere from 500 to 100) of these magnetically sensitive particles to store a single binary digit. The increased reduction of the amount of particles required to record data is highly limited by the precision of the read/write head (the miniature device that reads and records data onto the recording medium) because the magnetic field which is used by the drive's read/write head to read and/or record (write) data is such that it already tentatively borders nearby data.
Should it be shrunk much further in an attempt to increase precision, the likelihood of data corruption would increase vastly. Research by various parties has been on-going to find a workable solution to recording data onto much fewer or even single particles for some time now. A hard drive may record data onto the Hard Disk Drive by applying a sufficient magnetic field to the section of the recording medium (which is suspended upon the Hard Disks platter) such that the data (a series of ones and/or zeros which correspond to the information being stored) is recorded onto the medium by aligning the specified particles to the desired magnetic pole (north or south). In doing so, any previous data which was present is therefore destroyed.
Perpendicular verses Longitudinal
Ever since the late 1980's and early 1990's magnetic media drive manufacturers have been researching the feasibility of switching from longitudinal to perpendicular recording techniques. The advantage is clearly one of capacity: when longitudinal magnetic particles are packed together, they take up much more space than if they were to stand upright, if they stood perpendicular to the platter. More than merely a matter of initial capacity gain, perpendicular recording technology avoids a problem which has been well known in the field for many years: the super-paramagnetic effect (SPE), which affects magnetically charged particles of such small size as that used in Hard Disk Drives. "The super-paramagnetic effect is a phenomenon observed in very fine particles, where the energy required to change the direction of the magnetic moment of a particle is comparable to the ambient thermal energy" (source: Wikipedia.org).Many theories have cropped up over the years as to what density magnetic particles (described by a disks areal density) may achieve before becoming subject to SPE. At present it is suggested that anything from 100Gbit/inch2 to 150Gbit/inch2 is the physical limitation for longitudinal Hard Disk Drives, although perpendicular media solutions have been made as high as 230Gbit/inch2.
In the layering of the magnetic particulates atop a magnetic suspension layer and orienting the particles perpendicular to the platter, the recording medium can pack many more magnetically sensitive particles together in the same space than previously possible whilst keeping SPE at bay. Perpendicular recording technology does not however preclude SPE from limiting capacity in the future, more than anything perpendicular recording technology can been described as a way to give manufacturers breathing room to develop more permanent technological solutions such as holographic lithography or a multilayered recording medium. Traditional recording media manufacture consists of the spreading of recording material over a disk platter via a centrifugal force induced by spinning the platter whilst the recording material is placed atop its surface. The centrifugal force would spread the recording material across the surface, evenly spreading it in all directions. Perpendicular recording media manufacture on the other hand requires a much different technique.
The exact manufacturing process of perpendicular recording media is unsurprisingly a closely guarded secret, especially considering its recent arrival on the marketplace. From patents filed at the United States Patent and Trademark Office (USPTO), it can be taken that the predominant technique involves the laminating of magnetic and non-magnetically charged metals such as chromium, cobalt, platinum and alloys of similar; sandwiching unique layers to affect the desired result – a recording medium such that the magnetic particles are aligned perpendicular to the platter. In US patent number 6387483, filed by the NEC Corporation of Tokyo; it describes the technique as follows:The perpendicular magnetic recording medium of the embodiment is formed by laminating a Cr film, a soft magnetic under layer film, and a perpendicular magnetizing film on a substrate in this order. (Source: USPTO no. 6387483)
In longitudinal media manufacture too, laminating multiple supportive metals is achieved; in perpendicular media however, the difference is the magnetizing film as described above. Whereas traditional lamination ordinarily serves only to prevent wear and noise (both electro-mechanical and audible noise), in perpendicular media manufacture it would appear that at least some of the lamination process is used to magnetize the magnetic media particles to a perpendicular orientation. Precisely how the reorientation of magnetic media particulate is accomplished is not easy to determine, most probably because the technology is so new that such details are sketchy at best and obscure or guarded at worst. This fact is not at all surprising concerning a new technology such as perpendicular magnetic media development.
The future of storage technology
Perpendicular magnetic media technology as discussed earlier is merely a temporary solution, to find more permanent solutions we must look to much more advanced technologies. One such technology is patterned magnetic media. The process of patterned magnetic media aims to make singular magnetic particulates the object of recording bits, you will remember that current technologies requires approximately 500 to 1000 magnetic particles to store a single bit. The object of patterned media is to cut this dramatically down to a single particle per bit. Advantages of such a technology are such as reduced statistical noise associated with granular media and more increased areal density (as much as 64Gbit/inch2).
Patterned magnetic media aims to prevent the SPE barrier, or at least further decrement its effect through the use of so-called mesas and valleys. The technique uses the creation of barriers between magnetic particles, thereby avoiding the SPE complication which affects closely packed particles. Holographic Storage (a.k.a. Holographic Lithography) too is a technology that aims to increase storage capacity which is also under heavy research, and claims to be a much more permanent solution. Unlike Patterned Magnetic Media, Holographic Storage is a revolutionary step away from magnetic media and previous optoelectronic technologies.
Hard Disk Drives will always be subject to inertia and centrifugal force induced by the moving parts of the drives mechanical components (platter, read/write head), Holographic Storage has no such issues; the holographic process uses lasers in replacement of the read/write head of a Hard Disk Drive and the media itself requires no momentum (unlike the platters in Hard Disk Drives).
Such holographic storage is far from realisation, in fact it is postulated by some that it may be as much as ten years before the technology can be made into a workable solution. In direct symmetry to early memory research, research on Holographic Storage technologies seems to have banded into two camps: one of super fast data retrieval and extraordinarily high capacity storage; no doubt there will be extremely profitable markets for both.
A Hard Disk Drive (HDD) is a device used by modern computers to permanently store information. The Hard Disk Drive is arguable the most essential part of a computer system in that all the information that is permanently stored is contained within its enclosure, including your computer's Operating System (OS). Thanks to Hard Disk Drives, long gone are the days when you would have had to keep all your programs and documents stored on removable media such as Floppy Disks or CD-ROMs.
Originally invented in the mid 1950's and made commercially available in 1956 by International Business Machines (IBM). Called RAMAC (Random Access Method of Accounting and Control), the first Hard Disk Drives contained as much as 50 platters which were 24 inches in diameter and were computers in their own right albeit with a single purpose – to store data. The entire unit which housed the hard drive was the approximate size of two large refrigerators placed side by side. In the 50 or so years since their invention, Hard Disk Drives have steadily and aggressively far out paced Moore's law. Which stipulates that memory in computers will increase by 100% approximately every 18 months. Hard Disk Drives on the other hand have increased capacity in the same period by approximately 130%, an increase of 100% every nine months in many cases. Such capacity increases are being threatened, however.
In the years since the first Hard Disk Drive very little has changed apart from logical steps in technology such as the increased speed or improved interfaces, the basic technology has changed very little. There have been no technological leaps, as it were, for Hard Disk Drives beyond their increased miniaturisation. Apart from miniaturisation and recording media improvements the Hard Disk Drive as a device is almost identical technologically speaking, to the very first, the RAMAC.Hard Disk Drives use a similar technology as is employed in audio and video cassettes. Such audio and video cassettes use a magnetic ribbon wound around a two wheels to store data. To access a particular portion of the data contained on the magnetic ribbon, the device must wind the tape such that the beginning of the section containing the data is underneath the device that reads the data (the magnetic read/write head). This process is called sequential data retrieval because in the process of accessing the particular data, the device must sequentially read each piece of data until the data it's looking for is found. This process is very time consuming and contributes to wear.
Hard Disks on the other hand use a circular disk-shaped platter upon which the magnetically sensitive compound is laid. Such platters are similar in concept to a Compact Disk (CD) in that the data they hold can be accessed randomly, that the recordable media is in a circular (disk) shape, and that the data is sectioned off into tracks and sectors. Data on a Hard Disk Drive can be accessed randomly because the recordable medium of Hard Disk Drives uses these separated tracks and sectors. By separating the data in such a way, it can be positioned at random intervals of the disk, depending upon the space requirements.
Anywhere from one to seven recordable platters are contained within a modern Hard Disk Drive's metallic enclosure. Hard Disk Drive platters are perfectly circular disks made from either an aluminium alloy or a more recently a glass ceramic substrate which is a ceramic disk suspended in a glass outer shell. Onto the surfaces of a disk's platter is laid a thin layer of a magnetically sensitive coating called the recording medium, in modern drives the mixture is a complex amalgam of different materials such as cobalt chromium platinum boron (CoCrPtB) and other such rare metals.
How does a Hard Disk Drive store data?
All information located on a computer is expressed as a series of ones and zeros (1/0), as binary digits (bits). Taking advantage of the nature of magnetic particles, that they can be polarised to magnetic north or south and that their magnetic poles can be alternated or switched when a sufficient magnetic field of the correct polarity is applied, Hard Disk Drives can store the very same sequence of bits onto a disk by polarising the required magnetic particles on the recording medium such that they represent the data being stored. Hard Disk Drives are sectioned off such that they contain both intersecting tracks and sectors. The purpose of which is to provide a logical data structure, to provide a way to distinguish between areas of data. Within each track there are a number of sectors. It is within these sectors of the Hard Disk which data is stored.
The platter of a Hard Disk Drive is coated with a magnetically sensitive coating comprised primarily of magnetically charged particles or filings which as a whole may be called the recording medium. These particulates can be magnetically aligned such that they represent binary digits, by inducing an electromagnetic field upon them via a devices read/write head. The recording media contains many billions of microscopic particles which when viewed extremely close resemble miniature metal filings. When a Hard Disk Drive records data onto the medium it takes many hundreds (usually anywhere from 500 to 100) of these magnetically sensitive particles to store a single binary digit. The increased reduction of the amount of particles required to record data is highly limited by the precision of the read/write head (the miniature device that reads and records data onto the recording medium) because the magnetic field which is used by the drive's read/write head to read and/or record (write) data is such that it already tentatively borders nearby data.
Should it be shrunk much further in an attempt to increase precision, the likelihood of data corruption would increase vastly. Research by various parties has been on-going to find a workable solution to recording data onto much fewer or even single particles for some time now. A hard drive may record data onto the Hard Disk Drive by applying a sufficient magnetic field to the section of the recording medium (which is suspended upon the Hard Disks platter) such that the data (a series of ones and/or zeros which correspond to the information being stored) is recorded onto the medium by aligning the specified particles to the desired magnetic pole (north or south). In doing so, any previous data which was present is therefore destroyed.
Perpendicular verses Longitudinal
Ever since the late 1980's and early 1990's magnetic media drive manufacturers have been researching the feasibility of switching from longitudinal to perpendicular recording techniques. The advantage is clearly one of capacity: when longitudinal magnetic particles are packed together, they take up much more space than if they were to stand upright, if they stood perpendicular to the platter. More than merely a matter of initial capacity gain, perpendicular recording technology avoids a problem which has been well known in the field for many years: the super-paramagnetic effect (SPE), which affects magnetically charged particles of such small size as that used in Hard Disk Drives. "The super-paramagnetic effect is a phenomenon observed in very fine particles, where the energy required to change the direction of the magnetic moment of a particle is comparable to the ambient thermal energy" (source: Wikipedia.org).Many theories have cropped up over the years as to what density magnetic particles (described by a disks areal density) may achieve before becoming subject to SPE. At present it is suggested that anything from 100Gbit/inch2 to 150Gbit/inch2 is the physical limitation for longitudinal Hard Disk Drives, although perpendicular media solutions have been made as high as 230Gbit/inch2.
In the layering of the magnetic particulates atop a magnetic suspension layer and orienting the particles perpendicular to the platter, the recording medium can pack many more magnetically sensitive particles together in the same space than previously possible whilst keeping SPE at bay. Perpendicular recording technology does not however preclude SPE from limiting capacity in the future, more than anything perpendicular recording technology can been described as a way to give manufacturers breathing room to develop more permanent technological solutions such as holographic lithography or a multilayered recording medium. Traditional recording media manufacture consists of the spreading of recording material over a disk platter via a centrifugal force induced by spinning the platter whilst the recording material is placed atop its surface. The centrifugal force would spread the recording material across the surface, evenly spreading it in all directions. Perpendicular recording media manufacture on the other hand requires a much different technique.
The exact manufacturing process of perpendicular recording media is unsurprisingly a closely guarded secret, especially considering its recent arrival on the marketplace. From patents filed at the United States Patent and Trademark Office (USPTO), it can be taken that the predominant technique involves the laminating of magnetic and non-magnetically charged metals such as chromium, cobalt, platinum and alloys of similar; sandwiching unique layers to affect the desired result – a recording medium such that the magnetic particles are aligned perpendicular to the platter. In US patent number 6387483, filed by the NEC Corporation of Tokyo; it describes the technique as follows:The perpendicular magnetic recording medium of the embodiment is formed by laminating a Cr film, a soft magnetic under layer film, and a perpendicular magnetizing film on a substrate in this order. (Source: USPTO no. 6387483)
In longitudinal media manufacture too, laminating multiple supportive metals is achieved; in perpendicular media however, the difference is the magnetizing film as described above. Whereas traditional lamination ordinarily serves only to prevent wear and noise (both electro-mechanical and audible noise), in perpendicular media manufacture it would appear that at least some of the lamination process is used to magnetize the magnetic media particles to a perpendicular orientation. Precisely how the reorientation of magnetic media particulate is accomplished is not easy to determine, most probably because the technology is so new that such details are sketchy at best and obscure or guarded at worst. This fact is not at all surprising concerning a new technology such as perpendicular magnetic media development.
The future of storage technology
Perpendicular magnetic media technology as discussed earlier is merely a temporary solution, to find more permanent solutions we must look to much more advanced technologies. One such technology is patterned magnetic media. The process of patterned magnetic media aims to make singular magnetic particulates the object of recording bits, you will remember that current technologies requires approximately 500 to 1000 magnetic particles to store a single bit. The object of patterned media is to cut this dramatically down to a single particle per bit. Advantages of such a technology are such as reduced statistical noise associated with granular media and more increased areal density (as much as 64Gbit/inch2).
Patterned magnetic media aims to prevent the SPE barrier, or at least further decrement its effect through the use of so-called mesas and valleys. The technique uses the creation of barriers between magnetic particles, thereby avoiding the SPE complication which affects closely packed particles. Holographic Storage (a.k.a. Holographic Lithography) too is a technology that aims to increase storage capacity which is also under heavy research, and claims to be a much more permanent solution. Unlike Patterned Magnetic Media, Holographic Storage is a revolutionary step away from magnetic media and previous optoelectronic technologies.
Hard Disk Drives will always be subject to inertia and centrifugal force induced by the moving parts of the drives mechanical components (platter, read/write head), Holographic Storage has no such issues; the holographic process uses lasers in replacement of the read/write head of a Hard Disk Drive and the media itself requires no momentum (unlike the platters in Hard Disk Drives).
Such holographic storage is far from realisation, in fact it is postulated by some that it may be as much as ten years before the technology can be made into a workable solution. In direct symmetry to early memory research, research on Holographic Storage technologies seems to have banded into two camps: one of super fast data retrieval and extraordinarily high capacity storage; no doubt there will be extremely profitable markets for both.
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