Tuesday, March 31, 2009

Intel Server and workstation processors


Intel® Server Processors

Intel® server processors deliver enhanced, energy-efficient performance for data-intensive business applications. Powering a range of multi-core 64-bit servers¹, Intel server processors enable you to optimize and scale computing environments to maximize server utilization to workload, while providing you with headroom for growth.

Intel® Workstation Processors

Changing ideas into reality just became faster. Workstations based on the Intel® Xeon® processor W5580, built on the new Intel® Microarchitecture, codenamed Nehalem, deliver intelligent performance features that scale performance to meet your most daunting workstation tasks. Design, model, create, and visualize faster on innovation platforms powered by Intel.


Mobile, professional, expert—which processor is right for your workstation needs?

Powerful digital workbench: Intel® Xeon® processor 5500 series

Intel® Xeon® processorDesigned specifically for workstations, the Intel® Xeon® processor W5580 series with intelligent performance creates a new category, the digital workbench, combining high performance computing (HPC) and workstation features into a single powerful innovation platform.

With digital workbenches, users can:

  • Create virtual wind tunnels
  • Simulate virtual drop test
  • Virtually test for manufacturability and assembly
  • Virtually test ideas with customers with photo-realistic digital mockups

Entry professional performance: Intel® Xeon® processor W3500 series and Intel® Core™2 processor family

Intel® Xeon® processor Intel® Core™2 Quad processor
Designed for single processor workstations, the Intel® Xeon® processor W3500 series, with intelligent performance features delivers the scalable performance necessary for premium single processor workstation experience;

enabling digital content creation, engineering, and financial users to create new ideas faster than ever before.

Intel® Core™2 processor family provides entry workstation users a functional feature set that delivers a rich workstation experience for entry design and development.

Workstation platforms product brief

Learn more about Intel® workstation and mobile workstation processors.

Workstation performance

Discover how the intelligent performance of the new Intel® Xeon® 5500 series processors enables workstation users to work better, faster, and smarter.

Performance on the move:
Intel® Centrino® 2 with vPro™ technology and Intel® Core™2 mobile processor

Intel® Centrino® with vPro™ technology Intel® Core™2 Extreme processor
  • Get the highest performing mobile workstation processor optimized for people on the move.¹
  • Enjoy great graphics and visualization with enhanced 3D and high-definition video capabilities.
  • Experience mobility made better, designed for the longest possible battery life and excellent wireless connectivity.

Intel Desktop processors

The Intel® Core™2 processor family


The Intel® Core™2 processor family delivers unrivaled performance and breakthrough energy efficiency. The Intel® Core™2 processor family are Intel's newest processors, built using 45nm technology with hafnium-infused circuitry which improves performance even further.¹ Just imagine the possibilities.



Featured product
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The highest performing desktop processor on the planet.¹ Shatter the limits of desktop computing with the intelligent performance of the Intel® Core™ i7-965 processor Extreme Edition, the smartest way to blast through highly-threaded games and applications.


Intel® Core™ i7 processor Extreme Edition
Conquer the world of extreme gaming with the fastest processor on the planet: the Intel® Core™ i7 processor Extreme Edition.¹ With faster, intelligent multi-core technology that responds to your workload, it delivers an incredible breakthrough in gaming performance.

Intel® Core™ i7 processor
With faster, intelligent multi-core technology that automatically applies processing power where it's needed most, new Intel® Core™ i7 processors deliver an incredible breakthrough in PC performance. They're the best desktop processors on the planet.¹

Intel® Core™2 Extreme processor
For extreme computing. Enjoy revolutionary levels of performance enabling vivid, high-definition experiences and multi-tasking responsiveness from state-of-the-art Intel dual-core and quad-core technologies.

Intel® Core™2 Quad processor
Multimedia enthusiasts, prepare to enthuse. Bring quad-core performance to your desktop with the Intel® Core™2 Quad processor. It's the ideal engine for highly threaded entertainment applications and highly productive multitasking.


Intel® Core™2 Duo processor
The power to perform. With power-optimized enabled dual-core technology and exceptional energy efficiency, the Intel® Core™2 Duo processor excels running the most intense applications.



Intel® Pentium® processors Family


Intel® Pentium® processors give you the ability to do more.

Featured product
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With Intel® dual-core technology at speeds up to 2.50 GHz.

Intel® Pentium® processor
The Intel® Pentium® processor delivers great desktop performance, low power enhancements, and multitasking for everyday computing.


Intel® Celeron® processor family

Get proven technology and exceptional value, with the Intel® Celeron® processor family.

Featured product
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The Intel Celeron processor 450 is now available at speeds up to 2.20 GHz.

Intel® Celeron® processor
The Intel® Celeron® processor-based desktop platforms offer a robust computing experience together with the outstanding quality and reliability you expect from Intel.




Definitions

  • CPU
  • Heat Sink
  • Fan
  • Computer Hardware Information about computer Motherboards
  • Ram
  • Hard Drive
  • CD-Rom

CPU


Also known as a processor or microprocessor the CPU was first developed by Intel in 1974 and is short for Central Processing Unit. The computer CPU is responsible for handling all instructions and calculation it receives from other hardware components in the computer and software programs running on the computer. Below is a graphic example of what the original Intel Pentium processor looks like.
Today there are several different manufactures of computer processors. However, Intel and AMD are the leaders in the PC market.
  • Additional information and help with computer processors can also be found on our CPU help page.
  • Additional information about installing a computer hardware including a computer processor can be found on document CHADD.

Many new computer users may improperly call their computer and even sometimes their monitor a CPU. When referring to your computer or monitor it is proper to refer to them as either computer or monitor and not CPU.

Heat sink

Computer heat sink
An electronic device that incorporates either a fan and/or a peltier device that allows a hot device such as a processor to keep cool. There are two types of heatsinks: active and passive.

Active heatsinks utilize power and are usually a fan type or some other peltier cooling device. If you are looking to purchase an active heatsink, it is recommended that you purchase fans with ball-bearing motors that often last much longer than sleeve bearings.

Passive heatsinks are 100% reliable, as they have no mechanical components. Passive heatsinks are made of an aluminum-finned radiator that dissipates heat through convection. For Passive heatsinks to work to their full capacity, it is recommended that there is a steady air flow moving across the fins. To the right is an example image of a heat sink that is both active and passive.

Fan

A fan mounted directly over the integrated-circuit chip containing a computer's central processing unit to prevent overheating.

Computer Hardware
Information about computer Motherboards.


Quick links

Motherboard ABCs
AT / ATX differences
Troubleshooting
Motherboard definitions

MOTHERBOARD ABCs

The motherboard is the main component found in PC and Macintosh computers. The motherboard is what allows various hardware components to transfer information to each other. As computers advanced, so did motherboards; below is a listing of the various Motherboard form factors.

Full-AT
Baby-AT
LPX
Full-ATX
Mini-ATX
NLX

Full-AT (12" wide x 13.8" deep) Matches the original IBM AT motherboard design, which only fits into full size AT or tower cases only, not being produced much any more, if any.

  • This form factor is no longer produced because it cannot be placed into the popular Baby-AT chassis.

Baby-AT (8.57" wide x 13.04" deep) Almost the same as the original IBM XT motherboard with modifications in the screw hole position to fit into AT style case, with connections built onto the motherboard to fit the holes in the case.

  • Specific placement of the keyboard and the I/O slots.
  • This board also cannot be placed into the slimline case.

LPX (9.00" wide x 13.00" deep) Developed by Western Digital when making motherboards, which was duplicated by many other manufacturers and is no longer made by Western Digital.

  • The LPX motherboard riser card contains all of the expansion slots.
  • Placement of the video, parallel, two serial and PS/2 connections have changed locations.

Full-ATX – (12" wide x 9.6" deep) / Mini-ATX – (11.2" wide x 8.2" deep) The official specifications were released by Intel in 1995 and was revised to version 2.01 in February 1997. The ATX form factor is an advancement over previous AT style motherboards. Therefore requires a new case design. ATX is not an abbreviation, it is actually a trademark which belongs to Intel.

  • The ATX motherboard has a stacked I/O connector panel mounted on the motherboard.
  • On a socket 7 ATX motherboard, the socket has been placed a further distance from the expansion slots, allowing for long boards to be placed in easier.
  • Single keyed internal power supply connector. This is the Molex power connector, ATX 2.01. Standby voltage needs to be greater than 720 mA. The connector now cannot be placed in improperly. While the Molex power connector allows for 5v and 3.3v to be connected, it is recommended that only a 3.3v be connected to the motherboard.
  • Relocation of the memory and the CPU creating better ventilation and easier upgrade.
  • Power management possible with proper BIOS support.

NLX (Supports motherboards with overall dimensions of 9.0" x 13.6" [maximum] to 8.0" x 10.0" [minimum]) Implemented in 1998 by Intel and is similar to the LPX form factor; however, includes several new improvements.

  • Support for the Pentium II
  • Support for AGP
  • Support for USB.
  • Support for DIMM.
  • Easier Access to internal components
  • Support for motherboards that can be removed without using tools.
AT / ATX DIFFERENCES

Below is some of the ways in determining if your motherboard is an AT motherboard or an ATX motherboard.

The Keyboard:

AT Motherboard = 5 pin large connector
ATX Motherboard = 6 pin mini connector.

MB Power Connector:

AT Motherboard = Single Row two connectors 5v & 12v
ATX Motherboard = Double row single connector 5v,12v, and 3.3v.


RAM


RAM (random access memory) is the place in a computer where the operating system, application programs, and data in current use are kept so that they can be quickly reached by the computer's processor. RAM is much faster to read from and write to than the other kinds of storage in a computer, the hard disk, floppy disk, and CD-ROM. However, the data in RAM stays there only as long as your computer is running. When you turn the computer off, RAM loses its data. When you turn your computer on again, your operating system and other files are once again loaded into RAM, usually from your hard disk.

RAM can be compared to a person's short-term memory and the hard disk to the long-term memory. The short-term memory focuses on work at hand, but can only keep so many facts in view at one time. If short-term memory fills up, your brain sometimes is able to refresh it from facts stored in long-term memory. A computer also works this way. If RAM fills up, the processor needs to continually go to the hard disk to overlay old data in RAM with new, slowing down the computer's operation. Unlike the hard disk which can become completely full of data so that it won't accept any more, RAM never runs out of memory. It keeps operating, but much more slowly than you may want it to.

How Big is RAM?

RAM is small, both in physical size (it's stored in microchips) and in the amount of data it can hold. It's much smaller than your hard disk. A typical computer may come with 256 million bytes of RAM and a hard disk that can hold 40 billion bytes. RAM comes in the form of "discrete" (meaning separate) microchips and also in the form of modules that plug into holes in the computer's motherboard. These holes connect through a bus or set of electrical paths to the processor. The hard drive, on the other hand, stores data on a magnetized surface that looks like a phonograph record.

Most personal computers are designed to allow you to add additional RAM modules up to a certain limit. Having more RAM in your computer reduces the number of times that the computer processor has to read data in from your hard disk, an operation that takes much longer than reading data from RAM. (RAM access time is in nanoseconds; hard disk access time is in milliseconds.)

Why Random Access?

RAM is called "random access" because any storage location can be accessed directly. Originally, the term distinguished regular core memory from offline memory, usually on magnetic tape in which an item of data could only be accessed by starting from the beginning of the tape and finding an address sequentially. Perhaps it should have been called "nonsequential memory" because RAM access is hardly random. RAM is organized and controlled in a way that enables data to be stored and retrieved directly to specific locations. A term IBM has preferred is direct access storage or memory. Note that other forms of storage such as the hard disk and CD-ROM are also accessed directly (or "randomly") but the term random access is not applied to these forms of storage.

In addition to disk, floppy disk, and CD-ROM storage, another important form of storage is read-only memory (ROM), a more expensive kind of memory that retains data even when the computer is turned off. Every computer comes with a small amount of ROM that holds just enough programming so that the operating system can be loaded into RAM each time the computer is turned on.


Hard Drive

The hard drive is what stores all your data. It houses the hard disk, where all your files and folders are physically located. A typical hard drive is only slightly larger than your hand, yet can hold over 100 GB of data. The data is stored on a stack of disks that are mounted inside a solid encasement. These disks spin extremely fast (typically at either 5400 or 7200 RPM) so that data can be accessed immediately from anywhere on the drive. The data is stored on the hard drive magnetically, so it stays on the drive even after the power supply is turned off.

The term "hard drive" is actually short for "hard disk drive." The term "hard disk" refers to the actual disks inside the drive. However, all three of these terms are usually seen as referring to the same thing -- the place where your data is stored. Since I use the term "hard drive" most often, that is the correct one to use.

CD-Rom

Compact Disc-Read-Only Memory, a type of optical disk capable of storing large amounts of data -- up to 1GB, although the most common size is 650MB (megabytes). A single CD-ROM has the storage capacity of 700 floppy disks, enough memory to store about 300,000 text pages.

CD-ROMs are stamped by the vendor, and once stamped, they cannot be erased and filled with new data. To read a CD, you need a CD-ROM player. All CD-ROMs conform to a standard size and format, so you can load any type of CD-ROM into any CD-ROM player. In addition, CD-ROM players are capable of playing audio CDs, which share the same technology.

CD-ROMs are particularly well-suited to information that requires large storage capacity. This includes large software applications that support color, graphics, sound, and especially video.

Saturday, March 28, 2009

A Leptop Computer


A laptop (also known as a notebook) is a personal computer designed for mobile use small enough to sit on one's lap.A laptop includes most of the typical components of a desktop computer, including a display, a keyboard, a pointing device (a touchpad, also known as a trackpad, or a pointing stick), speakers, as well as a battery, into a single small and light unit. The rechargeable battery required is charged from an AC/DC adapter (ie, a wall wart) and typically stores enough energy to run the laptop for several hours.

Laptops are usually shaped like a large notebook with thicknesses between 0.7–1.5 inches (18–38 mm) and dimensions ranging from 10x8 inches (27x22cm, 13" display) to 15x11 inches (39x28cm, 17" display) and up. Modern laptops weigh 3 to 12 pounds (1.4 to 5.4 kg); older laptops were usually heavier. Most laptops are designed in the flip form factor to protect the screen and the keyboard when closed. Modern 'tablet' laptops have a complex joint between the keyboard housing and the display, permitting the display panel to twist and then lay flat on the keyboard housing. They usually have a touchscreen display and some include handwriting recognition or graphics drawing capability.

Laptops were originally considered to be "a small niche market" and were thought suitable mostly for "specialized field applications" such as "the military, the Internal Revenue Service, accountants and sales representatives". Battery-powered portable computers had just 2% worldwide market share in 1986. But today, there are already more laptops than desktops in businesses, and laptops are becoming obligatory for student use and more popular for general use. According to a forecast by Intel, more laptops than desktops will be sold in the general PC market as soon as 2009.

Contents


History

As the personal computer became feasible in the early 1970s, the idea of a portable personal computer followed. In particular, a "personal, portable information manipulator" was imagined by Alan Kay at Xerox PARC in 1968 and described in his 1972 paper as the "Dynabook".

The I.B.M. SCAMP project (Special Computer APL Machine Portable), was demonstrated in 1973. This prototype was based on the PALM processor (Put All Logic In Microcode).

The I.B.M. 5100, the first commercially available portable computer, appeared in September 1975, and was based on the SCAMP prototype.

As 8-bit CPU machines became widely accepted, the number of portables increased rapidly. The Osborne 1 used the Zilog Z80, weighed 23.5 pounds (10.7 kg). It had no battery, only a tiny 5" CRT screen and dual 5¼" single-density floppy drives. In the same year the first laptop-sized portable computer, the Epson HX-20, was announced. The Epson had a LCD screen, a rechargeable battery and a calculator-size printer in a 1.6 kg (4 pounds) chassis. Both Tandy/Radio Shack and HP also produced portable computers of varying designs during this period.

The first laptop using the clamshell design, used today by almost all laptops, appeared in 1982. The $8150 GRiD Compass 1100 was used at NASA and by the military among others. The Gavilan SC, released in 1983, was the first notebook marketed using the term "laptop".

From 1983 onwards:

  • Several new input techniques were developed and included in laptops: the touchpad (Gavilan SC, 1983), the pointing stick (IBM ThinkPad 700, 1992) and handwriting recognition (Linus Write-Top, 1987).
  • some CPUs were designed specifically for low power use (including laptops (Intel i386SL, 1990), and were supported by dynamic power management features (Intel SpeedStep and AMD PowerNow!) in some designs.
  • Displays reached VGA resolution by 1988 (Compaq SLT 286) and 256-color screens by 1993 (PowerBook 165c), progressing quickly to millions of colors and high resolutions.
  • High-capacity hard drives and optical storage (CD-ROM followed CD-R and CD-RW and eventually by DVD-ROM and the writable varieties) became available in laptops soon after their introduction to the desktops.

Early laptops often had proprietary and incompatible system architectures, operating systems, and bundled applications, making third party hardware and software difficult and sometimes impossible to develop.

Classification

The general terms "laptop" or "notebook" can be used to refer to a number of classes of small portable computers:

By purpose and (approximately) by screen size:

  • Desktop replacement – emphasizes performance, is less portable, 15" and larger screen;
  • Standard laptop – balances portability and features, 13-15" screen;
  • Subnotebook – emphasizes portability, has fewer features, 13" or smaller screen.

By features:

  • Budget – a cheap, lower-performance standard-sized laptop;
  • Tablet PC – Has a touch-screen interface, may or may not have a keyboard;
  • Netbook – A cheaper, smaller ver sion of a subnotebook suited to Internet surfing and basic office applications.
  • Rugged – Engineered to operate in tough conditions (strong vibrations, extreme temperatures, wet and dusty environments).

As replacement


A desktop replacement computer is a laptop that provides most of the capabilities of a desktop computer, with a similar level of performance. Desktop replacements are usually larger and heavier than standard laptops. They contain more powerful components and numerous ports, and have a 15.4" or larger display. Because of their bulk, they are not as portable as other laptops and their operation time on batteries is typically shorter.

Some laptops in this class use a limited range of desktop components to provide better performance for the same price at the expense of battery life; in a few of those models, there is no battery at all, and the laptop can only be used when plugged in. These are sometimes called desknotes, a portmanteau of the words "desktop" and "notebook," though the term can also be applied to desktop replacement computers in general.

In the early 2000s, desktops were more powerful, easier to upgrade, and much cheaper in comparison with laptops. But in the last few years, the advantages have drastically changed or shrunk since the performance of laptops has markedly increased.In the second half of 2008, laptops have finally outsold desktops for the first time ever. In the U.S., the PC shipment declined 10 percent in the forth quarter of 2008. In Asia, the worst PC shipment growth went up 1.8 percent over the same quarter the previous year since PC statistics research started.

The names "Media Center Laptops" and "Gaming Laptops" are also used to describe this class of notebooks.

Notebook

Although the term Notebook is now often used interchangeably with the term Laptop, it was originally introduced to differentiate a smaller, thinner and lighter range of devices (comparable with a traditional paper notebook) which supplanted their larger counterparts.

Subnotebook

A subnotebook, also called an ultraportable by some vendors, is a laptop designed and marketed with an emphasis on portability (small size, low weight and long battery life) that retains the performance of a standard notebook. Subnotebooks are usually smaller and lighter than standard laptops, weighing between 0.8 and 2 kg (2 to 5 pounds); the battery life can exceed 10 hours when a large battery or an additional battery pack is installed.

To achieve the size and weight reductions, ultraportables use high resolution 13" and smaller screens (down to 6.4"), have relatively few ports, employ expensive components designed for minimal size and best power efficiency, and utilize advanced materials and construction methods. Some subnotebooks achieve a further portability improvement by omitting an optical/removable media drive; in this case they may be paired with a docking station that contains the drive and optionally more ports or an additional battery.

The term "subnotebook" is usually reserved to laptops that run general-purpose desktop operating systems such as Windows, Linux or Mac OS X, rather than specialized software such as Windows CE, Palm OS or Internet Tablet OS.

Netbook

Netbooks are laptops that are light-weight, economical, energy-efficient and especially suited for wireless communication and Internet access. Hence the name netbook (as "the device excels in web-based computing performance") rather than notebook which pertains to size.

Especially suited for web browsing and e-mailing, netbooks "rely heavily on the Internet for remote access to web-based applications" and are targeted increasingly at cloud computing users who rely on servers and require a less powerful client computer.[21]. While the devices range in size from below 5 inches to over 12, most are between 7 and 11 inches and weigh between 2 and 3 pounds.

Netbooks have a wide range of light-weight operating systems including Linux and Windows XP rather than more resource-intensive operating systems like Windows Vista as they have less processing power than traditional laptops.

Rugged Laptop


A rugged (or ruggedized) laptop is designed to reliably operate in harsh usage conditions such as strong vibrations, extreme temperatures and wet or dusty environments. Rugged laptops are usually designed from scratch, rather than adapted from regular consumer laptop models. Rugged notebooks are bulkier, heavier, and much more expensive than regular laptops, and thus are seldom seen in regular consumer use.

The design features found in rugged laptops include rubber sheeting under the keyboard keys, sealed port and connector covers, passive cooling, superbright displays easily readable in daylight, cases and frames made of magnesium alloys or have a magnesium alloy rollcage that are much stronger than plastic found in commercial laptops and solid-state storage devices or hard disc drives that are shock mounted to withstand constant vibrations. Rugged laptops are commonly used by public safety services (police, fire and medical emergency), military, utilities, field service technicians, construction, mining and oil drilling personnel. Rugged laptops are usually sold to organizations, rather than individuals, and are rarely marketed via retail channels.

Components

The basic components of laptops are similar in function to their desktop counterparts, but are miniaturized, adapted to mobile use, and designed for low power consumption. Because of the additional requirements, laptop components have worse performance than desktop parts of comparable price. Furthermore, the design bounds on power, size, and cooling of laptops limit the maximum performance of laptop parts compared to that of desktop components.

The following list summarizes the differences and distinguishing features of laptop components in comparison to desktop personal computer parts:

  • Motherboard – laptop motherboards are highly make- and model-specific, and do not conform to a desktop form factor. Unlike a desktop board that usually has several slots for expansion cards (3 to 7 are common), a board for a small, highly integrated laptop may have no expansion slots at all, with all the functionality implemented on the motherboard itself; the only expansion possible in this case is via an external port such as USB. Other boards may have one or more standard or proprietary expansion slots. Several other functions (storage controllers, networking, sound card and external ports) are implemented on the motherboard.
  • Central processing unit (CPU) – Laptop CPUs have advanced power-saving features and produce less heat than desktop processors, but are not as powerful. There is a wide range of CPUs designed for laptops available from Intel (Pentium M, Celeron M, Intel Core and Core 2 Duo), AMD (Athlon, Turion, and Sempron), VIA Technologies, Transmeta and others. On the non-x86 architectures, Motorola and IBM produced the chips for the former PowerPC-based Apple laptops (iBook and PowerBook). Some laptops have removable CPUs, although support by the motherboard may be restricted to the specific models. In other laptops the CPU is soldered on the motherboard and is non-replaceable.
  • Memory (RAM)SO-DIMM memory modules that are usually found in laptops are about half the size of desktop DIMMs. They may be accessible from the bottom of the laptop for ease of upgrading, or placed in locations not intended for user replacement such as between the keyboard and the motherboard.
  • Expansion cards – A PC Card (formerly PCMCIA) or ExpressCard bay for expansion cards is often present on laptops to allow adding and removing functionality, even when the laptop is powered on. Some subsystems (such as Wi-Fi or a cellular modem) can be implemented as replaceable internal expansion cards, usually accessible under an access cover on the bottom of the laptop. Two popular standards for such cards are MiniPCI and its successor, the PCI Express Mini.
  • Power supply – laptops are powered by an internal rechargeable battery that is charged using an external power supply. The power supply can charge the battery and power the laptop simultaneously; when the battery is fully charged, the laptop continues to run on AC power. The charger adds about 400 grams (1 lb) to the overall "transport weight" of the notebook.
  • Battery – Current laptops utilize lithium ion batteries, with more recent models using the new lithium polymer technology. These two technologies have largely replaced the older nickel metal-hydride batteries. Typical battery life for standard laptops is two to five hours of light-duty use, but may drop to as little as one hour when doing power-intensive tasks. Batteries' performance gradually decreases with time, leading to an eventual replacement in one to three years, depending on the charging and discharging pattern. This large-capacity main battery should not be confused with the much smaller battery nearly all computers use to run the real-time clock and to store the BIOS configuration in the CMOS memory when the computer is off. Lithium-Ion batteries do not have a memory effect as older batteries may have. The memory effect happens when one does not use a battery to its fullest extent, then recharges the battery.
  • Video display controller – on standard laptops video controller is usually integrated into the chipset. This tends to limit the use of laptops for gaming and entertainment, two fields which have constantly escalating hardware demands. Higher-end laptops and desktop replacements in particular often come with dedicated graphics processors on the motherboard or as an internal expansion card. These mobile graphics processors are comparable in performance to mainstream desktop graphic accelerator boards.
  • Display – Most modern laptops feature 12 inch (30 cm) or larger color active matrix displays with resolutions of 1024×768 pixels and above. Many current models use screens with higher resolution than typical for desktop PCs (for example, the 1440×900 resolution of a 15" Macbook Pro[34] can be found on 19" widescreen desktop monitors).
  • Removable media drives – a DVD/CD reader/writer drive is standard. CD drives are becoming rare, while Blu-Ray is not yet common on notebooks. Many ultraportables and netbooks either move the removable media drive into the docking station or exclude it altogether.
  • Internal storageHard disks are physically smaller—2.5 inch (60 mm) or 1.8 inch (46 mm) —compared to desktop 3.5 inch (90 mm) drives. Some new laptops (usually ultraportables) employ more expensive, but faster, lighter and power-efficient Flash memory-based SSDs instead. Currently, 250 to 320 GB sizes are common for laptop hard disks (64 to 128 GB for SSDs).
  • Input – A pointing stick, touchpad or both are used to control the position of the cursor on the screen, and an integrated keyboard is used for typing. External keyboard and mouse may be connected using USB or PS/2 (if present).

Docking stations

A docking station is a relatively bulky laptop accessory that contains multiple ports, expansion slots and bays for fixed or removable drives. A laptop connects and disconnects easily to a docking station, typically through a single large proprietary connector. A port replicator is a simplified docking station that only provides connections from the laptop to input/output ports. Both docking stations and port replicators are intended to be used at a permanent working place (a desk) to offer instant connection to multiple input/output devices and to extend a laptop's capabilities.

Docking stations became a common laptop accessory in the early 1990s. The most common use was in a corporate computing environment where the company had standardized on a common network card and this same card was placed into the docking station. These stations were very large and quite expensive. As the need for additional storage and expansion slots became less critical because of the high integration inside the laptop, the "port replicator" has gained popularity. The port replicator was a cheaper, often passive device that simply mated to the connectors on the back of the notebook and allowed the user to quickly connect his laptop so that his monitor, keyboard, printer and other devices were instantly attached. As higher speed ports such as USB and Firewire became common, the connection of a port replicator to a laptop was accomplished by a small cable connected to one of the USB or FireWire ports on the notebook. Wireless Port Replicators are available as well.

A recent variant of the port replicator is the combined power/display/USB hub cable found in the new Apple Cinema Display.

Standards

Some laptop components (optical drives, hard drives, memory and internal expansion cards) are relatively standardized, and it is possible to upgrade or replace them in many laptops as long as the new part is of the same type. Subtle incompatibilities and variations in dimensions, however, are not uncommon.Depending on the manufacturer and model, a laptop may range from having several standard, easily customizable and upgradeable parts to a proprietary design that can't be reconfigured at all.

In general, components other than the four categories listed above are not intended to be replaceable, and thus rarely follow a standard. In particular, motherboards, locations of ports, design and placement of internal components are usually make- and model-specific. Those parts are neither interchangeable with parts from other manufacturers nor upgradeable. If broken or damaged, they must be substituted with an exact replacement part. The users uneducated in the relevant fields are those the most affected by incompatibilities, especially if they attempt to connect their laptops with incompatible hardware or power adapters.

Intel, Asus, Compal, Quanta and other laptop manufacturers have created the Common Building Block standard for laptop parts to address some of the inefficiencies caused by the lack of standards.

Advantages

Portability is usually the first feature mentioned in any comparison of laptops versus desktop PCs. Portability means that a laptop can be used in many places—not only at home and at the office, but also during commuting and flights, in coffee shops, in lecture halls and libraries, at clients' location or at a meeting room, etc. The portability feature offers several distinct advantages:

  • Getting more done – using a laptop in places where a desktop PC can't be used, and at times that would otherwise be wasted. For example, an office worker managing his e-mails during an hour-long commute by train, or a student doing her homework at the university coffee shop during a break between lectures.
  • Immediacy – Carrying a laptop means having instant access to various information, personal and work files. Immediacy allows better collaboration between coworkers or students, as a laptop can be flipped open to present a problem or a solution anytime, anywhere.
  • Up-to-date information – If a person has more than one desktop PC, a problem of synchronization arises: changes made on one computer are not automatically propagated to the others. There are ways to resolve this problem, including physical transfer of updated files (using a USB stick or CDs) or using synchronization software over the Internet. However, using a single laptop at both locations avoids the problem entirely, as the files exist in a single location and are always up-to-date.
  • Connectivity – A proliferation of Wi-Fi wireless networks and cellular broadband data services (HSDPA, EVDO and others) combined with a near-ubiquitous support by laptops means that a laptop can have easy Internet and local network connectivity while remaining mobile. Wi-Fi networks and laptop programs are especially widespread at university campuses.

Other advantages of laptops include:

  • Size – laptops are smaller than standard PCs. This is beneficial when space is at a premium, for example in small apartments and student dorms. When not in use, a laptop can be closed and put away.
  • Low power consumption – laptops are several times more power-efficient than desktops. A typical laptop uses 20-90 W, compared to 100-800 W for desktops. This could be particularly beneficial for businesses (which run hundreds of personal computers, multiplying the potential savings) and homes where there is a computer running 24/7 (such as a home media server, print server, etc.)
  • Quiet – laptops are often quieter than desktops, due both to the components (quieter, slower 2.5-inch hard drives) and to less heat production leading to use of fewer and slower cooling fans.
Battery – a charged laptop can run several hours in case of a power outage and is not affected by short power interruptions and brownouts. A desktop PC needs a UPS to handle short interruptions, brownouts and spikes; achieving on-battery time of more than 20-30 minutes for a desktop PC requires a large and expensive UPS.

Disadvantages

Compared to desktop PCs, laptops have disadvantages in the following fields:

Performance

While the performance of mainstream desktops and laptops is comparable, laptops are significantly more expensive than desktop PCs at the same performance level.The upper limits of performance of laptops are a little bit lower, and "bleeding-edge" features usually appear first in desktops and only then, as the underlying technology matures, are adapted to laptops.

However, for Internet browsing and typical office applications, where the computer spends the majority of its time waiting for the next user input, even netbook-class laptops are generally fast enough.Standard laptops are sufficiently powerful for high-resolution movie playback, 3D gaming and video editing and encoding. Number-crunching software (databases, math, engineering, financial, etc.) is the area where the laptops are at the biggest disadvantage.

Upgradeability

Upgradeability of laptops is very limited compared to desktops, which are thoroughly standardized. In general, hard drives and memory can be upgraded easily. Optical drives and internal expansion cards may be upgraded if they follow an industry standard, but all other internal components, including the CPU and graphics, are not intended to be upgradeable.

The reasons for limited upgradeability are both technical and economic. There is no industry-wide standard form factor for laptops; each major laptop manufacturer pursues its own proprietary design and construction, with the result that laptops are difficult to upgrade and have high repair costs. With few exceptions, laptop components can rarely be swapped between laptops of competing manufacturers, or even between laptops from the different product-lines of the same manufacturer.

Some upgrades can be performed by adding external devices, either USB or in expansion card format such a PC Card: sound cards, network adapters, hard and optical drives, and numerous other peripherals are available. But those upgrades usually impair the laptop's portability, because they add cables and boxes to the setup and often have to be disconnected and reconnected when the laptop is moved.

Ergonomics and health

Because of their small and flat keyboard and trackpad pointing devices, prolonged use of laptops can cause repetitive straininjury.Usage of separate, external ergonomic keyboards and pointing devices is recommended to prevent injury when working for long periods of time; they can be connected to a laptop easily by USB or via a docking station. Some health standards require ergonomic keyboards at workplaces.

The integrated screen often causes users to hunch over for a better view, which can cause neck or spinal injuries. A larger and higher-quality external screen can be connected to almost any laptop to alleviate that and to provide additional "screen estate" for more productive work.

A study by State University of New York researchers found that heat generated from laptops can raise the temperature of the scrotum when balancing the computer on one's lap, potentially putting sperm count at risk. The small study, which included little more than two dozen men aged 21 to 35, found that the sitting position required to balance a laptop can raise scrotum temperature by as much as 2.1 °C (3.8 °F). Heat from the laptop itself can raise the temperature by another 0.7 °C (1.4 °F), bringing the potential total increase to 2.8 °C (5.2 °F). However, further research is needed to determine whether this directly affects sterility in men.

A common practical solution to this problem is to place the laptop on a table or desk. Another solution is to obtain a cooling unit for the laptop, these units are usually USB powered consist of a hard thin plastic case housing 1, 2 or 3 cooling fans (the whole thing is designed to sit under a laptop) which results in the laptop remaining cool to the touch, and greatly reduces laptop heat generation. There are several companies which make these coolers.

Heat from using a laptop on the lap can also cause skin discoloration on the thighs.

Durability

Due to their portability, laptops are subject to more wear and physical damage than desktops. Components such as screen hinges, latches, power jacks and power cords deteriorate gradually due to ordinary use. A liquid spill onto the keyboard, a rather minor mishap with a desktop system, can damage the internals of a laptop and result in a costly repair. One study found that a laptop is 3 times more likely to break during the first year of use than a desktop.

Original external components are expensive (a replacement AC adapter, for example, could cost $75); other parts are inexpensive—a power jack can cost a few dollars—but their replacement may require extensive disassembly and reassembly of the laptop by a technician. Other inexpensive but fragile parts often cannot be purchased separate from larger more expensive components.The repair costs of a failed motherboard or LCD panel may exceed the value of a used laptop.

Laptops rely on extremely compact cooling systems involving a fan and heat sink that can fail due to eventual clogging by accumulated airborne dust and debris. Most laptops do not have any sort of removable dust collection filter over the air intake for these cooling systems, resulting in a system that gradually runs hotter and louder as the years pass. Eventually the laptop starts to overheat even at idle load levels. This dust is usually stuck inside where casual cleaning and vacuuming cannot remove it. Instead, a complete disassembly is needed to clean the laptop.

Battery life of laptops is limited; the capacity drops with time, necessitating an eventual replacement after a few years.

Security

Being expensive, common and portable, laptops are prized targets for theft. The cost of the stolen business or personal data and of the resulting problems (identity theft, credit card fraud, breach of privacy laws) can be many times the value of the stolen laptop itself. Therefore, both physical protection of laptops and the safeguarding of data contained on them are of the highest importance.

Most laptops have a Kensington security slot which is used to tether the computer to a desk or other immovable object with a security cable and lock. In addition to this, modern operating systems and third-party software offer disk encryption functionality that renders the data on the laptop's hard drive unreadable without a key or a passphrase.

Other portable computing devices

There are several categories of portable computing devices that can run on batteries but are not usually classified as laptops: portable computers, keyboardless tablet PCs, Internet tablets, PDAs, Ultra Mobile PCs (UMPCs) and smartphones.






A Portable computer is a general-purpose computer that can be easily moved from place to place, but cannot be used while in transit, usually because it requires some "setting-up" and an AC power source. The most famous example is the Osborne 1. Also called a "transportable" or a "luggable" PC.

A Tablet PC that lacks a keyboard (also known as a non-convertible Tablet PC) is shaped like slate or a paper notebook, features a touchscreen with a stylus and handwriting recognition software. Tablets may not be best suited for applications requiring a physical keyboard for typing, but are otherwise capable of carrying out most tasks that an ordinary laptop would be able to perform.




An Internet tablet is an Internet appliance in tablet form. Unlike a Tablet PC, an Internet tablet does not have much computing power and its applications suite is limited—it can not replace a general purpose computer. Internet tablets typically feature an MP3 and video player, a web browser, a chat application and a picture viewer.

A Personal digital assistant (PDA) is a small, usually pocket-sized, computer with limited functionality. It is intended to supplement and to synchronize with a desktop computer, giving access to contacts, address book, notes, e-mail and other features.

An Ultra Mobile PC is a full-featured, PDA-sized computer running a general-purpose operating system.

A Smart phone is a PDA with an integrated cellphone functionality. Current smartphones have a wide range of features and installable applications.

Boundaries that separate these categories are blurry at times. For example, the OQO UMPC is also a PDA-sized tablet PC; the Apple eMate had the clamshell form factor of a laptop, but ran PDA software. The HP Omnibook line of laptops included some devices small enough to be called Ultra Mobile PCs. The hardware of the Nokia 770 internet tablet is essentially the same as that of a PDA such as the Zaurus 6000; the only reason it's not called a PDA is that it doesn't have PIM software. On the other hand, both the 770 and the Zaurus can run some desktop Linux software, usually with modifications.

Major brands and manufacturers

There is a multitude of laptop brands and manufacturers; several major brands, offering notebooks in various classes, are listed in the box to the right.

The major brands usually offer good service and support, including well-executed documentation and driver downloads that will remain available for many years after a particular laptop model is no longer produced. Capitalizing on service, support and brand image, laptops from major brands are more expensive than laptops by smaller brands and ODMs.

Some brands are specializing in a particular class of laptops, such as gaming laptops (Alienware), netbooks (EeePC) and laptops for children (OLPC).

Many brands, including the major ones, do not design and do not manufacture their laptops. Instead, a small number of Original Design Manufacturers (ODMs) design new models of laptops, and the brands choose the models to be included in their lineup. In 2006, 7 major ODMs manufactured 7 of every 10 laptops in the world, with the largest one (Quanta Computer) having 30% world market share.Therefore, there often are identical models available both from a major label and from a low-profile ODM in-house brand.


Sales

For year 2008 it is estimated that 145.9 million notebooks were sold, and in 2009 the number will grow to 177.7 million. The third quarter of 2008 was the first time when notebook PC shipments exceeded desktops, with 38.6 million units versus 38.5 million units.

See also