CRTs rarely provide support for digital (DVI) signals; DVI support is found primarily on LCDs. The advantage of digital signals for LCDs is of much less importance now than it was a few years ago. Analog (VGA) 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. Analog inputs, sometimes labelled D-Sub, have a D-shaped connector with 15 pins arranged in three rows.

Adjustability: Most CRTs sit on stands that let you tilt and swivel the screen, but LCDs are generally more flexible. Some include a swivel feature, many offer height adjustability, and most can tilt forward and backward. Some LCDs' 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.

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

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

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 bottom of the screen), as would be the case with normally proportioned displays.

Philips 170W4P

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.

Wireless: Some displays are doing away with cables completely. ViewSonic's Airpanel uses Microsoft's Smart Display technology to establish a wireless connection with a desktop computer. Somewhere between a tablet computer and a remote display, it gives you more freedom to move around.

ViewSonic Airpanel V110

Other: LCDs using Philips's LightFrame technology and various CRTs using high-brightness features allow you to increase the amount of light for a given window or the entire screen. This can be helpful when viewing movies or other graphics images. BenQ's FP591 has inputs for CompactFlash, SmartMedia, and SD/MMC removable media cards that let digital photo enthusiasts see their pictures without a PC.

BenQ FP591

BenQ FP591 USB 2.0 ports, compact media slots