How to buy laptop

Some feature to buy laptop

Processor: Intel's dual-core processors have helped laptops gain ground in the power department. In PC World tests, laptops using these dual-core processors performed considerably faster than laptops using single-core processors, particularly when multitasking. In newer notebooks you may see references to Core Duo, Core 2 Duo, and Core 2 Extreme, which represent steps up in computing power for laptops.

Some notebooks use AMD's Athlon Turion 64 X2 dual-core processor, which also supports improved performance. The Turion 64 X2 and the Core 2 Duo both provide 64-bit support, which will become increasingly useful as more 64-bit applications reach the market.

Low-end laptops offer Intel's Celeron M processor, which is generally not as speedy as the Core 2 Duo processors. And down below low-end are the new mobile processors that appear in netbooks (or mini-notebooks)--sub-$500 machines that run on low-power, low-cost 1.6-GHz Atom CPUs.

System memory: Unless you're buying on the cheap, a new laptop generally includes 2GB of system memory. Many notebooks today are available with 3GB of RAM or more. Before electing to upgrade to more RAM than that, be sure to check which version of Windows your new notebook uses. A 32-bit OS can't efficiently use more than 3GB of RAM. A 64-bit version can go higher. Outfitting your laptop with more RAM at the time you buy it is convenient and helps you extend its useful life.

Graphics memory: Portables can have either of two different types of video chip sets: dedicated video (which means a separate preinstalled graphics card) or integrated graphics. Dedicated video chip sets come from nVidia and ATI/AMD, whereas integrated graphics are typically from Intel. If you intend to use your laptop for even casual gaming, make sure that it has memory dedicated to graphics use, rather than relying on graphics that pull from main memory. Gamers need advanced 3D graphics chips, along with 512MB of dedicated graphics memory. High-end desktop-replacement notebooks have sophisticated desktop graphics capabilities, as well; in the past integrated graphics would work just fine for business purposes, but Windows Vista demands a more-powerful graphics subsystem.

Some laptops now offer Scalable Link Interface (SLI), which provides a means to run multiple graphics chips in one machine. Hybrid SLI, a technology offered by nVidia, involves two GPUs operating within a single notebook. The most basic version of Hybrid SLI already exists on Apple's new MacBook Pro laptop and on a couple of notebooks from Sony's VAIO line. With these machines you toggle between a high-powered discrete GPU for graphics-intensive work or play and an integrated GPU on the motherboard for low-demand graphics. A second implementation of Hybrid SLI will allow an integrated GPU, like nVidia's GeForce 9400M GS, to work in tandem with a discrete GPU for greater performance when needed--and then downshift to a lower-power mode when it isn't.

Screen: Some laptop screens continue to get bigger--and most have gone wide, too, enabling you to view spreadsheets or movies with ease. But other screens have gotten significantly smaller to accommodate all sorts of road-ready computing. Price is no longer much of a deterrent for any of these choices. Even budget shoppers can afford the luxury of high-resolution color: Portables with 14.1-inch and 15.4-inch wide screens now cost well under $1000. Most notebook manufacturers offer laptops with wide-screen panels, to permit better side-by-side document viewing as well as to display films at their proper aspect ratio. These days, netbooks come equipped with screens as large as 10.2 inches. Ultraportable notebooks max out at 13.3 inches. And anything between 13.3 and 17 inches qualifies as an all-purpose machine--a laptop that still fits in your bag. The new middle ground for all-purpose screens is 16 inches because screen of this size can display a true 1080p (1920-by-1080-pixel resolution) picture.

Battery: Laptop battery life continues to improve. In PC World's tests, laptops using a Core Duo or Core 2 Duo processor average roughly 3.5 hours on one battery charge. Keep in mind that manufacturers may improve their times by taking steps such as turning off wireless receivers, which tend to consume a lot of power. Also, check to see if the manufacturer's stated battery-life numbers are for its regular or extended-life battery--the latter kind of battery can last up to twice as long as a regular one. And remember that, in general, lighter laptops tend to have longer battery lives than big desktop-replacement notebooks do.

Keyboard and pointing device: Though you can get accustomed to almost any laptop keyboard, it's best to try before you buy. Thin-and-light notebooks usually have smaller-than-average keys spaced more closely than the keys on a desktop-replacement model, and their layouts may differ from a standard keyboard's. If you have largish hands, be aware that an ultraportable's keyboard may be difficult to use.

You probably won't be invited to choose between eraserhead and trackpad pointing devices; if you have a preference, look for manufacturers that use the pointing device you prefer on most of their products. A better option: Buy a USB mouse designed for laptops. It's a small investment, and your hands will thank you for it.

Optical and other drives: Most manufacturers offer laptops with rewritable DVD drives. But now that Blu-ray Disk has triumphed over HD DVD in the high-definition format wars, more notebooks are being configured with Blu-ray drives. If you need a floppy drive for some reason, you can buy a USB add-on drive for 20 bucks.

Hard drive: Even inexpensive netbooks now come with 60GB hard-disk drives (HDDs). Most all-purpose machines offer hard drives in the range of 200GB to 320GB, and ultraportables now pack solid-state drives (SDDs). Though SDDs are faster and lighter than HDDs, their capacities are considerably lower (maxing out at around 128GB) at a significantly higher cost. In today's market, an SSD adds about $1000 to a laptop's price tag over the cost of a similarly specced machine equipped with a larger-capacity platter-based drive. So, you need to balance speed and weight against price and storage capacity. Whichever choice you make, you'll find that hard-drive space fills up quickly, so you might want to consider buying a portable external drive as well.

Weight and bay design: Laptops range from 15-pound desktop replacement monsters to ultraportable lightweights that rely on external drives to come in at under 3 pounds. One-bay notebooks balance features and weight. Some laptops continue to offer the optical drive as a modular device, so you can swap it out for a second hard drive or a second battery.

When making a purchase, however, keep in mind that you should consider the weight not only of the laptop but also of the AC adapter, the extra batteries, any external modules, and their cables. Ultraportable notebooks have lightweight adapters, but they can weigh almost as much as a full-size notebook if you have to carry an external optical drive, too.

When you return to your desk, you can snap most laptops onto an extra-cost docking station or port replicator (prices range from $100 to $500). Doing so saves you from repeatedly having to plug in and unplug an external monitor, keyboard, mouse, and other desktop peripherals.

Communications: Few laptops come with a full set of legacy ports anymore. Serial ports are as rare as bigfoot sightings at this point, as are PS/2 ports (for a mouse or keyboard). Most notebooks still have one PC Card slot, though many now offer an ExpressCard slot as well. With new GPUs, many notebooks--and even some netbooks--now offer HDMI outputs.

Most laptops have at least two USB 2.0 ports; many offer four, and some up to six. A majority of notebooks include a four-pin FireWire (IEEE 1394) port for connecting an external drive or a digital-video camcorder. Others now include eSATA ports for high-speed data transfers.

Built-in ethernet now comes standard on all portables, with many models carrying gigabit ethernet. Many laptops also have built-in Bluetooth. Notebooks using the Intel Core Duo or Core 2 Duo processors--or AMD's Turion 64 X2 processor--include Intel's wireless 802.11a/b/g chip set.

Some laptops come with built-in wireless broadband wide-area networking, enabling them to access, for example, Verizon Wireless's EvDO Broadband Access service.

Most also include a multiformat flash card reader, which can read Secure Digital, MultiMediaCard, Memory Stick, Memory Stick Duo, and xD formats.