By Rick Broida
PC World (US) 

Here’s a little-known advantage to using Internet Explorer 8: It lets you access multiple Gmail accounts simultaneously and independently.

This is accomplished via the New Session option, which makes it possible to log onto Web sites that track your identity across different tabs–like Gmail.

In Firefox, for instance, you can’t have multiple Gmail accounts open in multiple tabs or Windows. If you sign into a second one, you’ll get signed out of the first one when you try to do anything.

Here’s how to take advantage of this IE8 perk:

1. Run Internet Explorer 8 and open Gmail. Make sure theRemember Meoption is unchecked when you sign in.

2. Press Alt-F, I, and then hitEnter. This will open a new Internet Explorer session (which for all intents and purposes is the same as a new IE window).

3. Open Gmail and sign into your second account, again making sure to uncheck Remember Me.

That’s all there is to it! This should work with other Webmail accounts and services that don’t like multiple sessions running simultaneously.

I know it’s not a perfect solution, especially if you prefer Gmail to remember your username and password from one session to the next. Here’s hoping Microsoft will further tweak IE’s New Session feature to support this option.

By the PC World Staff

The netbook market is new, and constantly in flux. In this netbook buying guide, we explain what models are available to you today.

Introduction

The term netbook, coined by Intel, conveys little useful information about this category of machines. Sure, they all have wireless networking, but so does every other laptop. What the term originally helped to identify was a class of small, ultralightweight, cheap-as-dirt mobile PCs.

Netbooks are tiny–usually between half and two-thirds the size of a garden-variety laptop–and they typically weigh around 2.5 pounds. With their cool, slim designs, they outclass some fancy ultraportables. And best of all, these diminutive laptops start at around $200 (in some cases $100, when purchased as part of a mobile broadband promotional deal).

But that doesn’t mean a netbook is for everyone. These are basic computing devices that will meet only basic computing needs. If you’re looking to do a little bit of word processing, maybe edit a few simple spreadsheets, and want to surf the Web, a netbook will suffice. But if you’re looking to edit high-resolution photos or work with video, a netbook isn’t for you: These systems have seriously limited processing power. You can listen to some tunes, but don’t expect first-ratesound. And you might be able to watch a few online videos, but you’ll be looking at a relatively tiny screen.

In determining what makes a netbook a netbook, and not an ultraportable laptop, we take several factors into consideration. Chief among them: price, size, and the CPU under its hood. But netbooks are constantly evolving, and we’re now on the cusp of next-generation models. Soon, we’ll see Atom processors outfitted with a discrete nVidia GPU (the Ion platform). And Intel isn’t the only chip maker in the netbook space: AMD is half-stepping into the territory with the Athlon Neo CPU. The distinguishing characteristics are in flux. With that in mind, here’s what you need to know when buying a netbook.

The Big Picture
The netbook market is new, and constantly in flux. We’ll explain the options available to you today. [ more ]

The Specs Explained
Just because netbooks are cheap, that doesn’t mean you have to expect poor performance. We’ll guide you through the choices you need to make in order to get the most out of your mini machine. [ more ]

Netbook Shopping Tips
Sure, some netbooks are cheap. But some also cost almost as much as full-fledged laptops. Our advice well help you find the right machine at the right price. [ more ]

The Big Picture

So many netbooks have reached market in the past year–and so many more are on the way–that selecting the right model can be a daunting task. There is no such thing as perfection in a category that is ultimately defined by compromises, but with a little grounding in the basic features of mini-notebooks, you can make an informed buying decision.

Key Features

Processor: With bargain-basement prices, svelte dimensions, and full-blown operating systems, models in the current crop of netbooks look great on paper. But the Intel Atom processor powering these machines can’t do anything much fancier than editing basic documents, sending e-mail, and browsing the Web. The standard configuration for the machines you’ll find on store shelves includes a 1.6GHz CPU with 1GB of RAM using Intel’s 945 chip set and running Windows XP–not exactly a performance powerhouse, but it works.

Making the most of your netbook is all about managing expectations. Don’t plan on playing modern PC games, editing huge pictures, or creating 1080p videos on these machines–at least not yet. Later this year, nVidia will release its Ion graphics platform, and AMD has already launched its Neo processor. These two mobile chips promise to boost netbook performance significantly, and may very well change the way we think about small, cheap computers.

 

Display: When our reviewer first encountered the original Asus Eee PC’s 7-inch LCD, he declared that he had to increase the magnification in his eyeglasses’ prescription–and spin the scroll wheel like a manic gerbil–just to read an everyday Web page.

Fortunately, times have changed. Even the smallest machines these days offer about 9 inches of viewable display area, with at least 800 pixels across. That is adequate for Web browsing, though the 10-inch screen available on most netbooks these days makes a real difference in the experience. And in the coming year, you’ll start to see more and more devices that straddle the netbook-ultraportable divide by offering 11- and 12-inch screens. However, screen coating is also a critical consideration. The HP Mini 2140′s glossy screen may look snazzy indoors, but in broad daylight–where many people would at least occasionally use it–the reflection can be dazzling, if not blinding.

Another characteristic to weigh is native resolution. The default setting for most netbooks is 1024 by 600 pixels. Though this slightly odd aspect ratio will work with most software, some programs require a different resolution to run properly. If you intend to run proprietary business apps that demand a specific resolution, make sure that the netbook you buy can support it. (The upcoming 11- and 12-inch models won’t run into this problem.)

 

Battery life: Though the Intel Atom CPU is by no means an energy hog, netbooks aren’t known for long battery life. That is partly because vendors typically try to keep costs down by providing a modest three-cell battery. If you’re lucky, a battery of that size will last 2.5 hours on one charge, judging from PC World Test Center results. So if you want to stay productive on your netbook while traveling, you’ll probably need to buy an oversize, extended-life battery to power your machine.

The best-selling Acer Aspire One is a case in point. As configured, this neat little machine sells for roughly $300; but if you want it to run longer (surviving a cross-country flight would be nice), prepare to shell out another $100 for an optional six-cell battery that effectively doubles its duration. The bigger battery adds a little more weight to the system, too: There’s roughly a 0.3-pound difference between three- and six-cell netbook batteries, but the longer life between recharges is worth the extra investment.

So far, Samsung has earned the laurels for producing netbooks that have the longest battery lives. We’ve seen some that last upwards of almost 8.5 hours in our lab tests.

You get one other bonus when you buy a bigger battery, in some models at least: The double-stuffed power source props up the netbook at a slight tilt, making ergonomic typing on the (usually) tiny keyboard a little easier.

 

Keyboard: Many netbooks come with serviceable, comfortable keyboards, despite their smaller size. A netbook’s keyboard is usually about 88 or 92 percent of a full-size QWERTY keyboard, but the layout and arrangement of those keys counts almost as much as their size. To see whether the layout and shape of a given keyboard will work for your fingers, you need to do some hands-on testing at a store. Of course, bigger keys are better for beefy digits–and netbooks that have 10-inch screens tend to offer the larger keyboards.

 

Software: Windows XP is largely the operating system of choice. Some foolhardy manufacturers have loaded netbooks with Windows Vista Basic while others offer up Linux flavors in their netbooks. Why Linux? For starters, it runs a little leaner than XP, which makes it perfect for a netbook’s anemic CPU. Second, it trims a few more dollars off the price of these already-inexpensive portables.

For the most part, Windows XP netbooks carry very little onboard software. A few machines we’ve seen came preloaded with OpenOffice.org–the free Java-based office suite–but few vendors care to match Samsung, whose netbooks have a fairly well constructed software suite (one that’s good by notebook standards, let alone netbooks). Almost all of the other netbooks we’ve examined require you to download, on your own, the software you want to use.

Expecting Windows Vista to work with a netbook’s puny processor is like expecting a baby with one hand tied behind its back to push a Buick up a hill. Nevertheless, HP originally packaged its 2133 netbook with Vista Business Edition–and no one was terribly surprised when its unimposing Via C7-M processor ran like an out-of-shape sprinter in a swimming pool full of Jell-O. Now Sony thinks it can get its new Atom-processor-based VAIO P mini-notebook (which it insists on calling a “lifestyle notebook” rather than a “netbook”) to run Windows Vista Basic. This is probably still a bit of a performance stretch, but initial tests show that Microsoft’s upcoming Windows 7 is a very plausible netbook OS.

We’ve also heard rumors that Google’s Android OS will find its way into netbooks this year, but no products are available as of this writing.

 

Wireless connectivity: If names mean anything, it seems reasonable to expect a “netbook” to deliver wireless broadband and constant connectivity. But that’s not quite the way things are today. Most netbooks do offer 802.11g wireless, which is more than adequate for basic needs around an office, airport, or hotel room. A couple of premium models offer 802.11n.

We’ve also started seeing netbooks that offer integrated 3G wireless broadband. It sounds great, but there is one big (and tightly knotted) string attached: A two-year contract will run you somewhere in the neighborhood of $2000 over the life of the deal and will wed you to a device that you might desperately want to replace long before the contract expires.

Our advice: If you crave wireless broadband performance, make sure that your netbook of choice supports an external solution. That way, you can buy a wireless broadband card and plug it into whatever machine you need. PC Express slots are still rare on netbooks, but USB ports aren’t. So even if you opt for a system that doesn’t accommodate PC Express, you can add a USB 3G adapter, which you can then use with any computer you own.

 

Optical drives: Forget about them. A netbook, by definition, lacks any form of optical drive. You may find drives on some devices that straddle the line between netbook and notebook, but you won’t find them on a true netbook.

 

The Specs Explained

When buying a netbook, you don’t have as many configuration options as you do with other laptops; these machines are limited. But that doesn’t mean that all netbooks are created equal.

Before you go shopping for a netbook, the first thing you should consider is how you’ll be using it. The first generation of netbooks targeted non-business consumers–especially students. After all, you can stuff one of these affordable task-specific portables in a bag, and it can take a beating. But machines of this class make sense for corporate users, too. Why lug a huge laptop through the halls of an office complex when all you need is a good keyboard and a wireless connection?

Such thinking has led vendors to divide netbooks into business and consumer subcategories. Corporate netbooks pack more premium components than their consumer counterparts. Of course, premium gear is expensive, and corporate netbooks command prices above $600.

Here’s a rough breakdown of some configuration options you’ll want to consider when making your purchase.

Important consideration: Keyboard size and layout. Yes, a netbook will have a small keyboard, but those keyboards are often quite comfortable. The layout and arrangement of the keys is almost as important as their size. If possible, do some hands-on testing at the store to see whether the layout and shape of a given keyboard will work for your fingers. You should also note the position of the mouse, touchpad, and any related buttons. Make sure they are convenient and comfortable. 

 

Important consideration: Screen size and coating. You’ll find netbook screens that range in size from 8 inches to 10 inches (and soon, as big as 12 inches) diagonally. 8 inches of real estate is adequate, but a 10-inch screen will make a real difference in the user experience. You should also consider the coating. A glossy screen may look snazzy indoors, but in broad daylight–where many people would at least occasionally use it–the glare on it can be blinding. 

 

Important consideration: Screen resolution.  Another characteristic to weigh is the screen’s native resolution. The default setting for most netbooks is 1024 by 600 pixels. Though this slightly odd aspect ratio will work with most software, some programs require a different resolution to run properly. If you intend to run proprietary business apps that demand a specific resolution, make sure that the netbook you buy can support it. 

 

Somewhat important: Operating system.  Windows XP is pretty much the standard, with some flavors of Linux available for most netbooks. Linux runs extremely fast by netbook standards. And its low overhead helps keep the retail price low on these little machines. But each netbook vendor deploys Linux differently on the systems it sells; most vendors also include a customized menu interface to streamline the user experience, and these menus can be obtrusive, limiting productivity. For your first netbook, unless you’re already interested in Linux, you may want to go for a model with Windows XP preinstalled. The cost difference is usually minimal, and XP is relatively speedy even on netbooks. Don’t, however, expect Windows Vista to run on a netbook’s puny processor. 

 

Somewhat important: Software.  For the most part, Windows XP netbooks carry very little onboard software. A few machines we’ve seen came preloaded with OpenOffice.org–the free Java-based office suite–but most netbooks we’ve examined require you to download, on your own, the software you want to use. 

 

Somewhat important: Hard drive.  Let’s be clear: You’re not going to find a terabyte hard drive on a netbook. But you can find models with reasonable amounts of storage space. We’ve tested models with drives as small as 60GB, and some with drives as big as 320GB. Most netbooks offer drives in the 120GB to 160GB range, which should be adequate for your storage needs. 

 

Somewhat important: Processor.  Netbooks are cheap for several reasons, and one of those reasons is the paltry processors they pack (an Intel Atom CPU in the 1.6GHz range is typical). That said, competition is on the way. AMD’s Athlon Neo CPU is a step up (as seen in HP’s Pavilion dv2) and we’re still waiting to hear word of netbooks sporting nVidia’s Ion platform. 

 

Somewhat important: Installed memory.  Another reason netbooks are cheap is because they don’t pack very much RAM. Look for 1GB of RAM. Anything more is beyond the realm of the standard small netbook.

 

Somewhat important: Wireless connectivity.  You might expect a machine called a netbook to deliver wireless broadband and constant connectivity, but you’d be wrong. Most netbooks do offer 802.11g wireless, which is more than adequate for basic needs; you’ll also find 802.11n wireless as an option, though it’s rare. If you crave wireless broadband performance, make sure that your netbook of choice includes a PC Express card slot or a USB port so you can buy a wireless broadband card.

 

Netbook Shopping Tips

If you’re convinced a netbook will meet your needs, and are ready to start shopping, here are a few recommendations. Remember, netbook specifications don’t vary as greatly as those of a regular laptop. These specifications will meet the needs of the average netbook user.

A 1.6GHz Intel Atom processor. This CPU isn’t going to pack a ton of power, but it will suffice for your basic computing needs. Most recent netbooks use Intel’s 1.6GHz Atom N270 CPU, but you can also find some models with the 1.66GHz Atom n280, which also has a faster frontside bus speed (667MHz versus 533MHz in the N270). In our performance tests, though, the difference between these two processors was negligible.

 

Supplemental battery. Vendors usually try to keep costs down by providing a modest three-cell battery, which will last about 2.5 hours, if you’re lucky. If you want to stay productive on your netbook while traveling, you’ll probably need to buy an oversize, extended-life battery to power your machine. You can find optional six-cell batteries for about $100. Keep in mind that these batteries not only boost the price of a netbook, they also increase its weight.

 

A 10-inch screen. You’ll find netbooks with screens smaller than 10 inches, and these models will suit some people just fine. But if you can, opt for a larger model; that slight bit of extra room will make a noticeable difference.

 

A 120GB hard drive. Yes, you’ll find netbooks with 60GB hard drives. But don’t limit yourself to such a small amount of storage when you can find models with 120GB–or larger–hard drives for the same price.

 

A well-laid out keyboard. You know you’ll be compromising on size when you purchase a netbook, and that applies to the keyboard, too. But smaller doesn’t have to mean unusable. Look for a model with a keyboard that is well designed and nicely laid out. Make sure the mouse buttons are sensibly positioned, too.

 

At least two USB ports. Many netbooks offer three, but some of the smaller models have only two. You don’t need to settle for less than that.

SAN FRANCISCO – Though Nintendo’s revamped DSi has been out in Japan since the start of November, Americans won’t get to enjoy its new features-including a slimmer profile, a VGA camera, and music playback via internal memory or an SD Card-until “well into 2009″.

But though we don’t necessarily condone it, the reality is that geeky gamers have long enjoyed music playback on the Nintendo DS. One method of doing so is to use MoonShell, a homebrew media player that supports MP3, Ogg Vorbis, and AAC files (the DSi supports only AAC).

To use MoonShell, you’ll need the hard-to-find Revolution for DS (aka R4)-an unofficial cartridge used for hacking the Nintendo DS handheld game machine. The R4 is a Slot-1 cartridge that reads data from removable microSD cards.

– Pop your microSD card into the provided USB card reader, insert it in your PC’s USB port, and update the software (currently v1.18).

– Download and install Moonshell.

– With SD card still mounted, copy music files into the root directory of the card.

– Eject the USB drive, put the SD card back into the R4. Power on, open up Moonshell, and pick a song!

– For more information on DS homebrew and storage devices, visit the Nintendo DS Homebrew Wikipedia page.

As for upgrading from my DS Lite, I reserve final judgment for when the DSi is officially released in the US. But currently, the new changes aren’t terribly compelling. For starters, DSi will have a shorter battery life compared to DS Lite and will sell for a higher price- US$179 as opposed to $129. Finally, the DSi will no longer be compatible with Slot-2 games or devices, such as GBA games or Guitar Hero: On Tour.

Before you drop hundreds or thousands of dollars on the wrong flat-panel HDTV, read our comprehensive breakdown of everything you need to know. Our advice might just help you save some money.

The Big Picture

HDTVs are available in a variety of flavors, including front- and rear-projection, but flat-panel sets have emerged as the most popular option by far. What’s not to like? You can get a big, beautiful picture from a display thin and light enough to hang on a wall. And the picture isn’t the only attractive thing: Prices have dropped over 20% in the past year alone.

If you decide that a flat-panel HDTV is the way to go, you still have to determine which kind to buy: plasma or LCD. For screens smaller than 42 inches diagonal, your only choice is LCD. But for screens of 42 inches or larger, it’s a matter of assessing which technology better suits your viewing conditions and preferences–and your budget.

Almost all sets on the market now, both plasma and LCD, are wide-screen models. Translation: Such sets have a 16:9 ratio of screen width to screen height (aspect ratio), which is the standard for HDTV and very close to the ratio used for most modern movies. As a result, the displays are more rectangular than the traditional, almost-square 4:3 sets of the past.

Plasma
Essentially all current plasma displays offer HDTV resolution. Screen sizes begin at 37 inches diagonal and typically range up to about 65 inches (occasionally moving up to the downright ridiculous 150-inch sets that companies trot out for trade shows). Prices start at around $800 and can reach about $15,000 for large, very high-end models, though $5000 to $7000 would be a more typical top price for 60- to 65-inch units.

Typically you get what you pay for in both plasma and LCD. A budget plasma model will usually have lower contrast and poorer reproduction of black and of dark grays, yielding a picture with less punch and detail. A bigger problem with a bargain set is that it may do a worse job of upconverting regular standard-definition TV programs and DVDs to its native resolution. The resulting picture could look softer, coarser, or noisier than if it had better processing.

The most expensive plasmas in a given screen size are typically 1080p models, which offer 1920×1080 resolution. Whether that provides a visible improvement in picture quality over 720p, in either 1366×768 or 1024×768 resolution, depends on the screen size and viewing distance. The smaller the screen, the closer you must be to it to fully appreciate the benefit of a higher display resolution. For example, with a 50-inch screen you would have to sit within about 10 feet to perceive the difference between 1080p and 1366×768. That said, we recommend skipping the less expensive 720p models and buying one that supports 1080p, the resolution of Blu-ray Disc video. Even some online streaming services offer 1080p today; we expect more services to do so in the future.

Like CRTs (picture tubes), plasmas use phosphors to generate light, which means they can be subject to “burn-in”–or, at least, older plasma sets are susceptible. Burn-in occurs when a static image stays on the screen for a very long time; for example, it could be the health meter in a video game, or an annoying network logo that squats in the corner of your screen.

Fortunately, you can minimize the risk–or in most cases, nearly eliminate it–by keeping the contrast and brightness settings reasonable (almost all TV sets come out of the box with their contrast, brightness, color, and sharpness controls turned up way too high) and by using stretch modes to fill the screen when you’re watching 4:3 programming (though that will distort the picture). Plus, most of today’s plasma TVs use pixel-shifting strategies that continually move the image on the screen in imperceptibly tiny increments to prevent burn-in. Such technology should help–that is, unless you plan to watch NCAA March Madness nonstop. Then you have bigger issues.

One last thing to bear in mind with plasma sets is the audio. Most now come with speakers either built in or attached to the sides or bottom of the panel, but some remain strictly video displays with neither speakers nor any integrated TV tuner. In such cases you will need to factor those additional costs into your home-theater budget.

LCD
LCD screens range from desktop-friendly 15-inch models up to 65-inch wide-screen wonders complete with speakers and TV tuners. At screen sizes smaller than 30 inches, HDTV LCDs still come at a premium price relative to conventional picture-tube sets, but the cost difference is much smaller than it once was. A 26-inch high-definition LCD, for instance, could sell for as little as $400. (A 26-inch wide-screen display has about the same screen height as a 21-inch TV with a conventional 4:3 aspect ratio.) And in large screen sizes of 50 inches and up, LCDs are now price-competitive with plasmas. According to the DisplaySearch Monthly Global TV E-Tail Pricing & Specification Database, the global average Internet price for LCD TVs fell by an average of 22% as compared with last year.

LCDs continue to play catch-up with plasma models in picture quality, however. LCD sets often come under criticism for having lower contrast ratios than their plasma counterparts, as they have a tougher time reproducing deep black and dark grays. They also have much slower response times (expressed in milliseconds) than plasmas. That limitation can lead to blurring in fast-moving action scenes, something that sports and video-game fiends are likely to find problematic. New advances in LCD technology have largely overcome the problem in the best sets, however.

LCDs are often one to several inches thicker than plasmas and have a somewhat narrower effective viewing angle. (Plasmas, like CRTs, are easily viewable from well off to the side and do not exhibit any change in brightness as you stand up or sit down.) On the other hand, LCDs are immune to burn-in, easier to view in brightly lit rooms, and just about always include all the standard features of a conventional TV. LCDs also run cooler than plasmas, which minimizes the need for potentially noisy cooling fans.

Another bonus of LCDs is that they give you the freedom to set them up almost anywhere in your house. LCDs work well in bright-light situations that would be tough for most plasmas. If you want your TV to serve double duty as a huge monitor, consider that LCDs are about a quarter to a third lighter than plasmas of the same size, so they’re easier to tote between rooms.

The Specs Explained
Buying an HDTV requires more than just deciding how big a screen you want, looking at some sets, and purchasing the one with the best picture that fits your budget. An options explosion has littered the shopping landscape with numbers, features, and terminology that even experts sometimes have trouble tracking (not us, though). We’ve cut through the chaos to give you the information you need to get up to speed. When you’re finding your way in the high-def, A/V world, don’t just go for the gaudiest numbers–some are important, sure, but others aren’t. Let’s quickly walk through a few.

Important: Contrast Ratio
Contrast ratio refers to the brightest and darkest light values a display can produce at the same time. All else being equal, the higher the contrast ratio is, the better the quality is. All else is seldom equal, however.

Pumping up the maximum light output, for example, will increase contrast, but it won’t do anything to help pitiful black levels–that, in our opinion, is a much greater concern. LCDs in particular have a tougher time dealing with darks. So take contrast ratings as a very rough guide to be supplemented by eyes-on evaluation. LCD contrast-ratio specs start at about 600:1, while those for plasmas start at about 1000:1. Although ratings of 10,000:1 or better are becoming common for both types of displays, you should approach such claims with a healthy bit of skepticism.

Since no true standard method for measuring contrast ratio exists, manufacturer exaggeration is rampant. Independent reviews are a more reliable guide, but in the end you need to trust your own eyes. Keep in mind that when you’re on a showroom floor, you’re checking out the HDTVs under the store’s lighting conditions, not yours. Will you watch in a dark cave or in a well-lit, open space? Probably the smartest idea is to check the store’s return policy before buying.

Important: Aspect Ratio
The aspect ratio describes the relationship of screen width to screen height. Conventional sets have a 4:3 aspect ratio, whereas wide-screen models are 16:9. Wide screens are the future. For one thing, HDTV is a wide-screen format. For another, DVDs usually look better on wide-screen displays because nearly every movie made in the last 50 years was filmed in an aspect ratio of either 1.85:1 (very close to 16:9, which is 1.78:1) or 2.35:1 (even wider than 16:9).

Important: Video Inputs
The number and type of video inputs determine which sources you can use with the display.

Composite video: This input type has the lowest quality but the broadest compatibility. Any device that has video outputs will include composite video among them. Connection is made with a single 75-ohm coaxial cable between RCA jacks.

S-Video: S-Video offers better quality than composite video does, and most video sources except standard VCRs now have S-Video outputs. Connection is made with a special cable and multipin sockets.

Component video: This high-quality option is the minimum standard for connecting high-definition cable and satellite set-top boxes, as well as progressive-scan DVD and Blu-ray Disc players. It requires three 75-ohm coaxial cables of the same type used for composite video.

VGA (Video Graphics Array): This high-quality analog RGB connection is used primarily for computer connections.

DVI (Digital Video Interface): One of the highest-quality types of inputs. This digital video connection can attach to devices with HDMI outputs (see below) by means of an adapter. It may also be used for computer connections. Requires a special cable and multipin sockets. Some displays with a DVI input may work only with computers, so watch out for that if you plan to connect an HDTV source, such as an HD digital cable box or a Blu-ray Disc or HD DVD player. Another thing you need for guaranteed HDTV compatibility is compliance with the HDCP (High-bandwidth Digital Content Protection) system.

HDMI (High-Definition Multimedia Interface): Also of the highest quality, HDMI is DVI plus a digital audio and control link. HDMI is the dominant digital connection interface for HDTVs today. The big draw here is that you get a one-wire setup that pumps HD content into your other home-theater components too. This connection is provided on almost all current HD satellite receivers, HD cable boxes, and upconverting DVD players (those that provide 720p, 1080i, or 1080p output from regular DVDs), and it is the standard video connector for Blu-ray Disc players. The exact version of the HDMI input (for example, 1.1 or 1.3) is of little consequence on TV sets currently on the market. Of more importance to HDTV shoppers is how many HDMI inputs a TV has. Aim to get an HDTV with at least three or four HDMI inputs, to accommodate the multiple devices you’re bound to accumulate.

HDMI CEC: HDMI inputs may include support for the Consumer Electronics Control (CEC) protocol, which enables CEC-certified components to send control information back and forth to one another. This arrangement can allow single-remote–or even single-button–control of functions involving multiple components, such as a TV, DVD player, and A/V receiver. Manufacturers tend to have their own names for HDMI CEC, such as CE-Link (Toshiba) and Anynet (Samsung). In many cases the CEC functionality is restricted to components from the same maker, which obviously lessens the benefit in a mixed-brand system.

Important: Resolution
Non-CRT displays, such as plasmas and LCDs, are fixed-pixel arrays, meaning they have rows and columns of individual picture elements that turn on and off to produce the necessary patterns of light. Resolution is specified as the number of pixel columns by the number of pixel rows-640×480, for example, or 1280×720. Resolution and contrast ratio determine perceived picture detail.

Digital content currently is delivered in one of five formats: 480i, 480p, 720p, 1080i, and 1080p. The 480i format is the same as that used for standard analog TV, and when programming originally in 480i is delivered by digital cable or satellite to your home, it retains that format. DVDs are sometimes mastered in 480p, but mostly they are 480i; a progressive-scan DVD player can deinterlace 480i DVDs to create 480p output, however. The 720p and 1080i formats are used by satellite, cable, and over-the-air-broadcast high-definition content providers, as well as some advanced DVD players that upconvert 480i and 480p content. Blu-ray Discs output 1080p video, though Blu-ray players can deliver the content in 1080i or 720p format for displays that do not accept 1080p input.

Given that the price differential between 720p and 1080p has narrowed considerably, we recommend buying a set that supports 1080p. Your new HDTV represents a long-term investment. Some online streaming services, such as Vudu and Dish Networks’ on-demand options, are offering 1080p today, and we expect more services to follow in the future. If your budget can handle 1080p, go for it.

Generally speaking, a display is considered high-definition if it is wide-screen and has a total pixel count approaching a million. So 1920×1080 (1080p), 1280×720 (720p), 1366×768, 1024×1024, and 1024×768 are all examples of high-definition display resolutions. The larger the screen and the closer you sit to it, the more important its resolution becomes.

Somewhat Important: Screen Size
Size matters, don’t get us wrong. But just because you can afford a 65-inch monster, that doesn’t mean you should buy one. You need to factor in the screen size and where you plan to watch the TV. Having your nose pressed up against the display in a broom closet of a room is hardly “ideal viewing conditions.”

To determine the best viewing distance, and therefore how much space you’ll need in your TV room, remember this simple bit of math: Note the screen size in inches and multiply it by two. Calculators ready? Take, for example, a 52-inch set. The sweet spot for viewing is 104 inches away, or a little more than 8.5 feet from the screen (8.66666667 feet if you want to be nitpicky about it). You don’t have to be exactly on target; simply bear this in mind as you plan where to place your new set.

Somewhat Important: Built-In Tuners
Most current flat-panel displays include a tuner for conventional analog broadcast and cable-TV reception and for broadcast HDTV. A few, however, are strictly business–they’re monitors with no built-in tuner (more common for plasmas than for LCDs). That may not matter if you receive all your TV programming via satellite or cable, but if you want to watch broadcast TV over an antenna, be sure that the set you buy includes a TV tuner. Most sets also have built-in tuners for digital cable TV (referred to as ATSC digital tuners). Although such tuners have a standard for handling scrambled premium channels (for example, HBO), many sets do not support it, so be sure you know exactly what you are getting. If you’re interested in that capability, you may know about CableCard (a few sets in the recent past offered a CableCard slot). But CableCard is giving way to the new Tru2way standard, which can banish the external box if both your TV and your cable provider support it.

Somewhat Important: Refresh Rate
Refresh rate refers to the number of times per second a new image displays on the screen. The standard refresh rate for television in North America is 60 times per second, or 60 Hz (hertz), and until fairly recently that was it. Now, however, many high-end LCD HDTVs offer a 120-Hz refresh rate. Usually the TV set achieves the higher rate by interpolating new frames between the ones that are broadcast. The tactic helps minimize or eliminate the blurring of fast motion that sometimes occurs on LCDs because of their relatively slow response times (how long they take to switch between black and white or between dark gray and light gray). Done well, 120-Hz refresh can be very effective; but done poorly, motion can appear slightly unnatural. As always, look at a set and judge its performance before you buy. Also find out whether the 120-Hz processing is switchable, so that you can turn it off if you don’t like it or you don’t need it. As response times and video processing of LCDs improve, the need for refresh-multiplication is diminishing.

Because plasma sets have very fast response times, they don’t require 120-Hz processing (though it may start showing up in them simply for marketing reasons). A nonstandard refresh rate presents another potential benefit, however, when you’re viewing material that originated as film. Movie film is shot at 24 frames per second and displays in theaters at 48 Hz, with each frame flashed on the screen twice. But putting movies on TV at the standard refresh rate is a little tricky, since 24 does not divide evenly into 60. The conventional solution is to stagger the frame repetitions, displaying the first frame twice, the second three times, the third twice, and so on. Although such 2:3 (or 3:2) processing works pretty well, it imparts a subtle stutter to on-screen motion.

Typically, viewers are so accustomed to this artifact that it seldom jumps out; but once you notice the effect, it’s as plain and obvious as can be. The TV can eliminate it, yielding a slightly smoother impression, if the set has the ability to switch to a refresh rate that’s an even multiple of 24 Hz for film-based content. Pioneer plasmas, for example, run at 72 Hz for film material, and the 24-fps output options of some Blu-ray Disc players are designed to facilitate the same sort of processing. Since 120 Hz is an integral multiple of 24 Hz, the opportunity exists to do something similar in high-refresh-rate LCDs, depending on how the display’s interpolation processing is designed.

Minor: 24p Input
Some Blu-ray Disc players can provide 24-fps 1080p video from their HDMI outputs for discs mastered at 24 fps, matching the frame rate of the film original. If the TV connected to such a player can accept 24-fps 1080p (24p) video and can operate at a refresh rate that is an integral multiple of 24 Hz (such as 72 or 120 Hz), it can process the video to create slightly smoother motion than if it were to convert the footage to the standard 60-Hz refresh rate. The benefit is relatively subtle, however, and not very many TVs offer such processing yet; even some sets that accept 24-fps signals just convert them to 60 fps for display. Be sure you know what you’re buying.

Minor: Ethernet Port
Some HDTVs now provide ethernet ports, which can give you access to the Internet or to content (such as pictures) streamed over a home network. Features available via ethernet vary somewhat from manufacturer to manufacturer, so confirm what you’re getting before you lay out the cash.

Minor: USB Port
Some HDTVs now have USB ports. Usually they are intended for connecting to flash drives containing pictures, music files, or possibly updates to the TV’s internal operating software (firmware). The exact functions of USB ports vary somewhat from one TV to the next, so do some research prior to committing to a set.

Minor: Comb Filter Type
Comb filters are necessary in analog TV to separate color and luminance information without losing too much detail, but that’s not an issue in HDTV. The only time the comb filter comes into play is for analog TV reception or any signal coming in via a composite-video connection. For all other connections, it’s out of the loop. In any case, the comb filters in flat-panel TV sets are routinely very good these days.

Flat-Screen TV Shopping Tips
All right, you’ve made it this far. Here are key points to consider before you take the HD plunge.

Consider the alternatives: If you can live with a tabletop set that’s 10 to 18 inches–rather than four to seven inches–deep, DLP (digital light-processing) rear-projection sets can deliver solid performance in similar screen sizes and at lower prices. You just don’t hear about them as much because they’re not as sexy.

Think HDMI: Get a set with at least three or four HDMI (High-Definition Multimedia Interface) inputs. Doing so will ensure that you can connect it to multiple HD sources such as digital cable boxes, satellite receivers, and Blu-ray Disc players. Try to choose a set with at least some front- or side-accessible ports; such conveniences can make life much easier when it comes time to connect a device.

Compare displays using various input sources:Most flat-panel displays will handle HDTV and DVD signals well, but mediocre cable and satellite signals will give some of them fits. Don’t make a buying decision based solely on images generated from pristine sources, or based on what you see in the store.

Look for good black tones: When you’re comparison shopping, bring along a DVD of a movie containing some dimly lit night scenes. Use it to check for good black reproduction and the ability to render detail in near-darkness.

Get to know the remote: A good remote can be your best friend, a bad remote your worst enemy. (Well, okay, we’re exaggerating a little, but you get the idea.) Does it have backlighting or glow-in-the-dark buttons to help you see what you’re doing when the lights are turned down? How easy is it to find commonly used buttons by feel?

Check the video settings: Grab the TV’s remote, pull up the video-adjustment menu and look at the settings. If you thought the picture looked a little (or a lot) off on first viewing, try selecting the median settings for contrast, brightness, color, tint, and sharpness. Those probably won’t be optimum, but chances are they’re closer than what you found originally. A good display can easily look worse than a lesser one if it’s poorly adjusted. Repeat your tests using a variety of sources, including a dimly lit movie, if necessary. Also keep in mind that you’ll likely have to readjust the color settings for each source. Most HDTVs these days have input memories, so your set should keep the ideal settings for high-def movies on one input and your video games on another.