CNET monitor buying guide

When buying a monitor, you have two technology choices: CRT and LCD. But not for long. CRTs, the large, bulky units that have graced desktops since the advent of the computer age, are slowly but surely being replaced by slim and bright LCDs.

Even though some gamers and graphics pros are clinging to CRTs, the majority of mainstream PC users find LCDs more appealing--a trend that monitor manufacturers have noticed. Mainstream CRTs have become more and more difficult to find on store shelves and online, and most major manufacturers have discontinued their CRT lines altogether.

Despite their dwindling market share, CRT monitors still beat out LCDs in a few performance categories: color fidelity, viewing angles, and contrast. Where LCDs are often able to produce a limited number of colors (usually 16.7 million), CRTs are capable of displaying an infinite range, an advantage for exacting graphic artists. CRTs also offer unlimited viewing angles, while the brightness and contrast on most LCDs will drop off when viewed at large angles.

Other than the obvious benefit of size, LCDs offer significant advantages over CRTs. They provide a brighter screen, which really helps in brightly lit office environments; offer clearer, crisper text; and have no geometric distortion or flicker--problems often found on CRTs that cause eye fatigue. And LCDs have even caught up to CRTs in the area of displaying moving images; CRTs were once far superior, but the playing field is now nearly level, with many manufacturers offering faster response times, meaning that on most LCDs, moving images will be free of ghosting and distortion.

LCDs are still slightly more expensive than CRTs--a decent 19-inch LCD will cost approximately $250 to $300 compared to a 19-inch CRT's $150 to $200. However, a 19-inch LCD offers as much screen real estate as a 21-inch CRT, which would cost about the same $250. (Of course, those prices vary among manufacturers and resellers.)

New technologies, such as LED-backlit LCD panels, are slowly emerging on the market, as well, but the only ones we've seen thus far are too expensive for the average consumer--upward of $6,000. While LED-backlist displays are starting to show up on some select laptop models, we've yet to see a consumer LCD monitor feature the technology.

Due to the changing market and LCDs growing closer to matching the performance of CRTs, we've focused our attention and this buying guide on purchasing the LCD to fit your needs. In today's market, LCDs are the most relevant and widely available technology, though if you insist on buying a CRT, technology has advanced to the point where there is very little difference in performance among brands. In other words, unless you buy the absolute cheapest CRT, you should be happy with whatever you choose.

CRTs for Luddites CRT Reviews

With so many monitors to choose from, before you buy it pays to figure out what specs and features will be most important to you. These user profiles will start you off in the right direction.

Match your needs to one of these user profiles: Home user | Business user | Student | Digital photographer/graphic artist | Gamer | Video editor/movie buff

Home user

Home users need to balance price and performance. Extra features such as speakers or USB ports are an important consideration, and depending on where the computer is located, aesthetics may matter as well.

Price

Good color performance

Sharp text

Design/appearance

Video input

LCDs for the home

Business user

Businesses need some bang for the buck, but they are willing to pay for productivity. Bells and whistles are not as important as good image quality and adjustability for viewing comfortably at long stretches.

Large image area to display more information

Adjustability

Energy efficiency

Compact form factor

Reliability

LCDs for business

Student

Academic life often means cramped quarters, with a budget to match. Students need a lightweight, portable design; a small footprint, and image quality good enough for both working and playing.

Low cost

Small form factor

Easy to move

Video input optional, but handy

LCDs for students

Digital photographer/graphic artist

With too many monitors, what you see onscreen is not what you get from your printer. People working with digital images need excellent color fidelity and consistent results. These high-end LCDs offer near perfect color scales and some provide color calibration options and advanced adjustability.

Color calibration

Excellent screen geometry

Large display area

High resolution

LCDs for graphics pros

Gamer

It's all about speed for serious game players. Eye-popping image quality is essential, but a lightning-fast pixel response time is the key to keeping images sharp when the action starts.

Pixel response time

Color accuracy

Large display area

LCDs for gamers

Movie buffs

When digital DeMilles edit the key close-up in their master work, they want total artistic control, and they need crisp, accurate images. Movie buffs watching at home will want the same.

Pixel response time

Color accuracy

Large display area

Alternate signal inputs a plus

Wide aspect ratio

Front-panel inputs

LCDs for movie buffs

LCDs are no longer an item only the upper caste can afford: a good, 19-inch LCD can be had for around $250 to $300. When shopping for an LCD, some specifications and features are more important than others. Here are a few of the biggies.

Aspect ratio: The standard proportion in width to height for a computer monitor is 4:3, but some new displays have a wider format: 16:9 or 16:10, designed for viewing movies or HDTV in wide format. Note that a 17-inch wide-format panel has about the same vertical dimension and vertical pixel count as a normal 15-inch panel, so you get about 120 percent of the viewing area of a 15-inch panel. A 17-inch standard panel, however, has 130 percent of the viewing area of a standard 15-inch screen.

Contrast ratio: A spec much hyped by manufacturers (be suspicious of their claims), this is the difference in light intensity between the brightest white and the deepest black.

Digital and analog connections: LCDs are digital devices and thus have to convert analog (VGA) signals before they can be displayed. A graphics card with a digital video interface (DVI) can send the signal straight to the display in digital format--no conversion required. At this point, most monitors do such a good job of signal conversion that digital connections are not as important as they used to be.

Digital input

Analog input

Luminance: Brightness; a measure of how much light a panel can produce. Luminance is expressed in either nits or candelas per square meter (cd/m²). A measurement of 200 to 250 nits is OK for most productivity tasks; 500 nits is better for TV and movies.

Pixel-response rate: This refers to how quickly a pixel can change colors, measured in milliseconds (ms); the lower the milliseconds, the faster the pixels can change, reducing the ghosting or streaking effect you might see in a moving or changing image. In general, manufacturers' specifications rely on best-case scenarios; real-world performance could be slower. A maximum response time of 12ms to 15ms across the spectrum is required for gaming or viewing television and movies without ghosting or streaking. Manufacturers have debuted LCDs with response rates as fast as 2ms.

Portrait/Landscape modes: Some LCDs pivot so that the longer edge can go horizontal (landscape mode) or vertical (portrait mode). This feature can be useful for desktop publishing, Web surfing, and viewing large spreadsheets, but don't pay extra for it if you won't use it.

Portrait mode

Landscape mode

Resolution: Make sure you are comfortable with an LCD's native resolution before you buy it. Remember, an LCD that scales its image to a nonnative resolution will never look as good.

Viewing angle: The physical structure of LCD pixels can cause the brightness and even the color of images to shift if you view them from an angle rather than facing the screen directly. Take manufacturer's specifications with a grain of salt and make your own observations if possible; viewing-angle issues become more critical as panel size increases.

Image quality, the most important feature of a monitor, is also the hardest to judge. Good is a subjective term, so relying on the judgment of reviewers (such as CNET) may not get you exactly what you want. Further, like a snowflake, every monitor is unique. There can be significant differences from one monitor to another--even among the same make and model. It's unrealistic to expect to run a comprehensive diagnostic on a monitor before you buy it, but here are some of the most important qualities to look for when choosing a monitor. We've also included a few simple tests you can do in the store to assess image quality.

What to look for

• Choose a monitor that automatically adjusts to the timing of an analog (VGA) signal. You want to see stable gray and patterned images with no pixel jitter.
• Find a monitor with good viewing angles. Colors and brightness should not change in the corners of the screen (where the viewing angle is the greatest).
• Pick a monitor that looks uniformly bright when viewing both dark and light images.

Tips and tricks: assessing LCD image quality

Check for dead pixels, ones that are always off. It's not uncommon for monitors to have one or two defective pixels--especially larger models--but you want as few as possible. Open a Web browser, in the address line type about:blank, and press Enter. Then press the F11 key to make it full screen. Look for small black specks that are not dust or debris on the screen. (Press F11 again to see the Explorer toolbars.)

An adequate graphics card is a necessity

What's going on inside your computer can have a profound effect on what's displayed on your monitor. If you hook up a 4- or 5-year-old PC to a top-of-the-line new monitor, there's a good chance your graphics card will need an upgrade to give you the best possible image quality. You'll need a card that supports your interface, be it digital or analog, and it will need to support your monitor's resolution--this is especially important on wide-aspect monitors, or monitors larger than 19 inches. Sometimes improving your graphics card's performance can be as easy as installing a driver upgrade from the manufacturer's Web site.

Digital (DVI) vs. analog (VGA)

Most LCDs provide support for digital (DVI) and analog (VGA) signals, but less expensive LCDs may offer only analog. The advantage of digital signals for LCDs is of much less importance now than it was a few years ago. Analog signal processing has improved to the point where only the most discerning eye can notice any difference. Most LCDs that support digital signals also support analog signals, so you won't need a special graphics adapter to use a DVI display.

Digital input

Analog input

To take advantage of the digital connection, you'll need a graphics adapter that has a DVI-I or DVI-D connector, and you may also need a DVI cable (many LCD monitors come with only an analog cable). DVI-D refers to a digital-only connection, and DVI-I means that the connector can carry either digital or analog signals.

Extra features

Adjustability: Most LCDs offer some degree of screen tilt, usually 30 degrees back and 5 degrees forward. Some include a swivel feature, many offer height adjustability, and some panels can also pivot between portrait and landscape modes, making legal-size documents and Web pages easier to view. LCDs can be attached to VESA-compatible mounts, which connect to third-party wall mounts or swinging arms.

Antireflective screen coatings: These glossy screen coatings, offered by certain manufacturers (Sony, Gateway, Acer), are supposed to reduce glare and ambient light reflection and provide a brighter, more vivid picture.

Audio: Some monitors offer audio functions, either as standard items or as optional accessories. These may include a headset jack, a volume control, or embedded speakers. In general, these speakers are of limited quality, and an inexpensive $30 speaker set from an office-supply or computer store will often provide much better sound.

Cable-feed systems: Many LCDs have some mechanism to manage signal and power cords.


HDCP: If you plan to watch high-definition, copyright-protected content via an HD DVD or Blu-ray player or through an HDTV signal on your LCD, you'll want to make sure it's an HDCP-compatible display. HDCP is an encryption system that protects HD content sent across HDMI or DVI connections. If your display doesn't support HDCP, then you'll either be staring at a blank screen or--if you use analog connections like VGA—-the best you'll get is a downsampled picture at a 960x450 resolution.

Memory card readers: A few monitors have media card readers built into the bezels. This is a handy addition for digital photo enthusiasts who want to see their pictures without a PC.


USB: Many displays have USB ports. Typically, they are not powered hubs, but simply convenient ports to connect a keyboard or a mouse, thereby reducing the tangle of cables that run back to the computer.


Video/TV: As work and entertainment products continue to converge, many monitors now have features designed to take advantage of television and movie content. Some include TV tuners and connectors for video signals from cable television systems or antennas. Some have connectors that accept composite or S-Video input signals from entertainment devices. Many multifunction monitor/TVs are able to display HDTV content.


Wide-screen format: Some CRTs and LCDs come in wide-screen formats designed to display more information and show HDTV and movies in their full width without letterboxing (blacking out the top and the bottom of the screen), as would be the case with normally proportioned displays.

When choosing a monitor, consider the company behind it.

First and foremost, make sure that the company offers a money-back guarantee. Most displays show their problems right out of the box or within the first month or two of use, so you want to be able to return it for a refund or an exchange with a minimum of hassle. Ninety days is standard, but this varies among retailers (many online retailers give you only 30 days). Also, beware of restocking fees.

Next, consider the warranty coverage. Most companies offer two to three years of parts-and-labor coverage; anything less is suspect. If you're buying an LCD, make sure that the backlight is covered by the warranty; manufacturers used to exclude them from coverage, but more and more now include them. LCD buyers should also note a company's policy on defective pixels; one or two defects are to be expected, but if there are many, you should be able to return the unit for exchange or a refund. Some companies deal with pixel problems on a "case-by-case" basis, meaning that they don't have a set policy. If you end up with a problematic display, you'll have to negotiate with the company. This is where the satisfaction-guaranteed return policy can become very important.

You're far less likely to need technical support for a monitor than for a computer system or a software program. Still, it's good to know that there's someone you can call if trouble arises; look for toll-free support numbers and weekend coverage.

Be sure to keep all of the packing material for your monitor. If you should ever need to return it or ship it back for warranty service, you'll need the packaging. Monitors can be bulky, fragile, and extremely difficult to protect adequately. You don't want to end up improvising.

To find out more about how warranties really stack up and what you should look for in a vendor's service and support, take a look at CNET's hardware warranty explainer.

Aperture grille: In some CRTs, the aperture grille is a series of wires stretched vertically down the inside of the monitor to mask the beams from the electron guns at the back of the tube. In other types of monitors, this function falls to a perforated metal plate called a shadow mask. Some users prefer the image quality of Sony Trinitron monitors, which use an aperture grille; others notice the faint horizontal shadows cast by the grille's tensioning wires and prefer other shadow-mask designs.

Bezel: The frame around a CRT's or LCD's screen.

CRT: Cathode-ray tube; a big bell of glass with electron guns at one end and a viewing screen at the other. Televisions and computer displays both use this imaging technology and are often simply called CRTs.

Convergence: Color CRTs rely on three separate electrical beams to project simultaneous red, green, and blue images; these combine to form a full-color image. If these beams are not precisely aligned, the red, green, and blue portions of the image may not overlap correctly, degrading the overall image quality. When the three beams converge correctly at all points on the display, you get a perfect image.

Dead/stuck pixel: A pixel on an LCD that is either permanently on (stuck) or permanently off (dead).

Display size: A display's length (in inches or centimeters) taken diagonally from one corner to the opposite corner. Unless it specifically states viewable screen area, a CRT's measurement encompasses the full face of the picture tube, including the part concealed by the bezel. On an LCD, only the viewable screen is measured.

Dot pitch: In CRTs, the distance from one pixel to the next-nearest one. The larger the dot pitch, the grainier an image looks.

Electron gun: A color CRT contains three electron guns that shoot electron beams, causing red (R), green (G), or blue (B) phosphors on the inside front of the screen to light up.

Footprint: The amount of space a monitor takes up on your desk, including the display and its base.

HDCP: High-bandwidth Digital Content Protection. Copy-protection scheme developed by Intel to be used in conjunction with DVI and HDMI connections.

LCD: Liquid-crystal display; created by sandwiching electrically reactive, liquid-crystal material between two electrodes. The substance can be darkened or lightened by applying and removing current.

Liquid crystal: A material with some of the properties of solid crystals, such as diamonds, and some of the properties of liquids, such as water. As a result, the material can both flow and affect the path of light, depending on how the individual molecules are aligned.

Molecule: The smallest portion of a material. For some materials, the physical size and shape of the individual molecules affect the overall properties of the material. For example, the individual molecules of liquid-crystal material can alter the path of light and can be induced to align in specific ways in response to physical or electrical influences. It is these characteristics that make them useful in creating displays.

Native resolution: The physical structure of some types of displays, including LCDs and plasma panels, defines how many pixels can be displayed at once. The display produces the sharpest picture when used at its so-called native resolution. Other types of displays, such as CRTs, create pixels independently of the physical structure of their screens and do not have a native resolution. As a result, a CRT's image quality is generally the same across a range of resolutions.

Nits: A unit of measure for luminance (a monitor's brightness); equivalent to candelas per square meter (cd/m²).

Phosphor: A substance that can produce red, green, or blue light when excited by an energy source, such as the electron beam in a CRT. Phosphors are arranged as either dots or stripes on the inside face of a CRT screen.

Pixel: In a CRT, phosphors grouped in RGB triads (one each of red, green, and blue) are called pixels. The hundreds of thousands to millions of pixels in a display create images.

Refresh rate: The frequency at which a CRT's electron guns redraw the image; measured in hertz (Hz). One hertz equals one cycle per second; a 70Hz refresh rate means that the entire screen is redrawn 70 times per second.

Resolution: For both CRTs and LCDs, the number of pixels in the whole image. For example, a resolution of 1,280x1,024 pixels means that 1,024 lines are drawn from the top to the bottom of the screen, and each of these lines is made up of 1,280 separate pixels.

Screen geometry: A description of how accurately lines and shapes are represented on the display. LCDs almost always have perfect geometry because the display information is mapped to specific physical pixels on the display. CRTs may have problems with screen geometry; larger screens and flat-faced models have particular difficulty controlling electron beams with precision. As a result, vertical lines may be noticeably curved at the edges of the display, and circles may appear oval or egg-shaped. The best CRT monitors include controls that let you adjust the screen geometry; still, it can be difficult to adjust it perfectly in all regions of the screen.

Shadow mask: A metal plate with holes in it that selectively blocks the beams from the electron guns in the back of a CRT.

Stripe pitch: Monitors using an aperture grille or striped mask have phosphors arranged in vertical stripes. Stripe pitch is the distance from a stripe of a given color to the next stripe of the same color. A smaller stripe pitch means that the monitor can display higher-resolution images more accurately.

Stuck/dead pixel: A pixel on an LCD that is either permanently on (stuck) or permanently off (dead).

Subpixel: Full-color displays are made by combining red, green, and blue light in varying degrees to produce different shades of colors. In a display with a fixed pixel structure, such as LCDs or plasma panels, the red, green, and blue light comes from adjacent cells in the display's physical structure. The light from these three subpixels--one for each color--combine to create a single pixel. There are also pixel structures that do not rely on three subpixels.

SVGA: Supervideo graphics array; a display mode with a resolution of 800x600 pixels.

SXGA: Superextended graphics array; a display mode with a resolution of 1,280x1,024 pixels.

TFT: Thin-film transistor; refers to the switching devices placed in each liquid-crystal cell in an active-matrix LCD. TFT screens are brighter and more readable than passive-matrix LCDs, but they consume more power and are generally more expensive.

Trinitron: A type of CRT developed by Sony that differs from standard tube types in that it employs an aperture grille instead of the usual shadow mask.

UXGA: Ultraextended graphics array; a display mode with a resolution of 1,600x1,200 pixels.

VGA: Video graphics array; a display mode with a resolution of 640x480 pixels.

Viewable area: The diagonal length of a CRT's viewable screen.

XGA: Extended graphics array; a display mode with a resolution of 1,024x768 pixels.