Key features
Laptop Processors: The central processing unit (CPU) is sometimes described as the most important chip in the computer. It contains the arithmetic and logic unit (ALU), so the computer can do calculations, and the control unit that controls the flow of data between the ALU and memory. There's a lot of competition between manufacturers of processors and the speeds they offer, but the plain fact is that while it is heavily featured in the marketing literature even the slower processors (1.4 to 1.6GHz) are fast enough for most uses, even though 3.0GHz is offered on many laptops. Money saved on processors might more usefully be spent on memory. There are two things that really matter with laptop processors: the balance struck between processor power and battery consumption, and the links to mobile technology that enable you to make the most of the laptop's portability. For the first, simply put, processors with the word mobile in their name are going to be the best choice, as in Mobile Intel Pentium 4 or Athlon XP Mobile. These use less power and run cooler (a definite plus in a laptop). For the second, Intel's combination of processor, chipset and wireless card technologies marketed under the brand name Centrino is hard to beat.
Laptop Hard drives: The computer uses the hard drive to store programs and files. The storage capacity of a basic 20GB hard drive is more than enough for most users. However, if you want to work with databases, or digital photos and video files then moving to a bigger hard drive, say 40 or 60GB, may be worthwhile. Some laptops are equipped with 120GB hard drives.
Laptop RAM: Random Access Memory (RAM) is where the computer stores applications that are running and data. Most laptops come with a standard 256MB of Random Access Memory. Moving up to 512 MB installed RAM is a must if you are intending to use the laptop for digital video or downloading music. Even if you are not, buying as much RAM as you can afford is one area of expenditure on computers that will always pay you back in the future. Check out the RAM capacity to see how much room you have for future upgrades.
Laptop Screen sizes: The liquid crystal display (LCD) screens used in laptops come in a range of sizes from 12" to 17" (measured diagonally). Smaller screens mean lighter and more portable laptops but a 15" screen is common. If you are going to be working on the machine a lot then a bigger screen with a decent resolution, say 1024/768, will be better for you in the long run. Higher resolutions mean you can fit more in on the screen, but you may find it harder to read. TFT (thin film transistor) screens are designed to perform better in bright light or sunlight and can produce clearer images. TFT is also called active matrix. TFT LCD screens are more expensive than LCD screens using passive matrix technology but give better displays. Widescreen display is useful for watching DVDs and for presentation work.
Graphics card: Graphics cards, also called video adapters, plug into a computer to give it display capabilities. Some laptops have a universal or shared memory function for display, but a graphics card containing 32 or 64MB of dedicated memory should be your target if you are going to be doing a lot of presentation work or are into gaming.
USB ports: Many laptops come with more than one USB port (four on some models) which makes connecting to peripherals a lot simpler. Newer models are also available with a Firewire connection to transfer digital information from camcorders or MP3 players for example.
Optical drives: CD-ROM (compact disc, read-only memory) is standard on almost all laptops. Most software programs are now offered on CD. Best for keeping the price of the laptop down.
CD-RW (compact disc, re-writeable) is better because not only can you read CDs you can also write and record data to them. Depending on the CD format you can record once (R) or multiple times (RW). Best if you want to copy music from your CDs into your notebook.
DVD-ROM (DVD, read-only-memory) can read DVD discs as well as CDs. Best if you want to watch DVD movies on your laptop and install software from DVD or CD.
Combination drives. Top of the range here is the DVD+RW/+R with CD-RW. With this you can write data to DVDs (which have up to seven times the storage capacity of a CD) and read DVDs and CDs as well. Best for maximum flexibility.
Removable medias: Some laptops now include slots for a variety of removable media like CompactFlash, Secure Digital or Memory Stick. These can be especially useful if you are using the laptop with other digital devices like cameras, camcorders and PDAs.
Batteries: Most laptops use Lithium Ion batteries. Battery life varies between laptops but somewhere between 2 and 5 hours, depending upon the number of things that you are asking the laptop to perform would be about average. Laptop battery recharging times will also vary - around 75 minutes is common - so buying a spare battery is well worth considering.
Docking stations: If you are using your laptop as a mobile replacement for your desktop then a docking station, sometimes called a port replicator, can save you a lot of bother with peripherals like printers, scanners and speakers. The laptop docking station is connected to all the peripherals and the laptop connects to it rather than each of them individually.
Touch sensitive mouse pads: This replaces the mouse on most laptops. Some users find that initially this can be difficult to operate. It is well worth testing out before you buy if you can.
Warranties: One place where you really might think about taking out this form of insurance is on a laptop. Reliability should not be any worse than any other computer product but the chances of having a mobile mishap are much greater than with desktop models. Screen damage is particularly easy to cause. Most manufacturers supply a warranty. Take this rather than a retailer one and extend it if you can.
Wireless technology: To be truly portable many laptop users take the Centrino route, Intel's mobile processor technology that allows you to use wireless networking. There are three wireless standards, of which the latest - 802.11g - is the most useful providing both a fast and stable connection and backwards compatibility with the older 802.11b standard. In theory, connection speeds of 54Mbps are possible. Realistically you will be looking at something between 15-20Mbps (less if you are using b and g together) but still very fast. An alternative option to the built-in solution is the addition of a wireless LAN card in your PC card slot to connect via hotspots.
Accessories
Mice: If you really can not cope with a touchpad then a separate mouse (wireless is best) could be the answer.
Memory sticks: Memory Sticks are an easy way to transfer small amounts data from your laptop to a desktop. They should not be treated as a means of permanent storage.
Carrying case: Not all laptops come with a laptop bag as standard.
Anti-virus software: Vital if you are going to make any connection to the internet and you value your data and security. Many laptops are sold with trial versions of products from major suppliers like McAfee or Symantec pre-installed.
Spare keyboard and monitor: If you find yourself using one of the smaller laptops as a desktop replacement you may find purchasing a larger keyboard will help. Wireless options are available. Plugging the laptop into a larger monitor can also help, and its worth remembering that many modern TVs can be used to give a larger monitor area.
Floppy disk drive: Still around, still working, and floppy disk drives are still the cheapest storage solution for data around. Investing in an external floppy disk drive means you can safely back-up very small amounts of data from your laptop and still make use those old floppies you have hanging around.
Printers: Mobile or not at some time you?re going to want to print. The choices to make are between inkjet (cheaper but lower quality), laser (more expensive but better quality, especially for images) and all-in-ones (which include extra features like scanning and copying).
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