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HP xb31 review: HP xb31

HP xb31

Brian Nadel
4 min read
Review summary
Hewlett-Packard's xb31 is a DLP projector that packs a lot of power for its size and weight. With a tested brightness of more than 1,200 lumens and an excellent 425:1 contrast ratio at its disposal, the xb31 can light up boardrooms and living rooms alike with bright, clear images. Unfortunately, performance problems, including image uniformity and color accuracy, prevent this projector from achieving top honors in our tests. The Mitsubishi XD50U is similarly priced, and it's a better all-around projector than the xb31. The lower-priced Dell 3200MP is also worth considering. The xb31 projector has a nice, compact design, with a rounded black, silver, and white case. It measures a scant 8.92 by 7.23 by 2.67 inches and weighs only 3.5 pounds. Throw in the cables and the power supply, and the projector still has a reasonable 4.7-pound travel weight.
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The xb31 projector has a nice, compact design. The six-button control panel is simpler than we'd like.

The pop-out front elevation foot and the threaded rear leg make quick work of aiming and leveling the projector during setup. All connection ports are located on the back panel.
On the projector's top, two helpful LEDs indicate overheating or an impending lamp failure.The six-button control panel is simpler than we'd like; common operations such as keystone correction and volume control must be accessed through the onscreen menus. These menus also let you change the settings for color saturation, sharpness, and tint. If you detect flicker, the xb31 lets you manually adjust the tracking to the signal timing of your source, but in our tests, the projector successfully tuned itself to our input source.
The xb31's comprehensive feature set belies its small size. While its native resolution is XGA (1,024x768 pixels), it can handle source resolutions ranging from 640x350 to 1,280x1,024. Supported video sources include NTSC, PAL, and SECAM, as well as HDTV. In addition to a 1.2X optical-zoom lens, it has a 31X digital zoom that produces exceptionally fine close-up detail.
The xb31 comes with ports and cables for composite video, S-Video, audio, and DVI sources. You also get a combo VGA-USB cable that lets you use the projector as a computer monitor. All the included cables come with Velcro wraps for convenient storage. The only things we missed were component-video inputs and cables.
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The xb31 comes with ports and cables for composite video, S-Video, audio, and DVI sources. The xb31's remote also includes an easy-to-use laser pointer.

Like the Dell 3200MP and the Optoma EzPro 737, the xb31's remote controls a notebook's cursor; it responds smoothly from as far away as 15 feet. The xb31's remote also includes an easy-to-use laser pointer.
Projecting images with the xb31 will be easier in bigger rooms. In our tests, the projector had to sit a long 7.4 feet away from our screen to project a standard, one-meter-diagonal image. The biggest image it could project clearly measured 24.6 feet diagonally.
HP promises a 1,500-hour life from the xb31's $349 lamp module. An LED on the projector's top panel signals lamp-life warnings at 1,000 and 1,500 hours; the onscreen menu provides a more precise meter. The lamp is theoretically easy to replace, requiring only a screwdriver; however, our unit's lamp cover was fastened so tightly that we couldn't unscrew it.
The xb31's imaging performance varied widely, from excellent to disappointing. Its tested brightness is a stunning 1,273 ANSI lumens, nearly matching HP's claim of 1,280 ANSI lumens. In our "--="" rel="nofollow" class="c-regularLink" target="_blank">&siteid=7&edid=&lop=txt&destcat=ex&destUrl=http%3A%2F%2Fwww%2Edisplaymate%2Ecom">DisplayMate tests, it showed 251 of 255 grayscale levels, but the grays looked slightly green. The xb31's color temperature averaged 5,167K--a bit warmer than we'd like. Its color chart lacked some light green, pink, reddish-orange, and dark blue shades. Certain color combinations, such as yellow on a cyan background, looked very poor. Our unit's relatively low, 62 percent uniformity was the biggest disappointment, and it was exacerbated by a prominent hot spot, dead-center, that extended to the lower-right corner.
CNET Labs contrast ratio tests  (Longer bars indicate better performance)
Dell 3200MP
Optoma EzPro 737
HP xb31
Mitsubishi XD50U
Gateway Projector 210

Operating the xb31 also has its ups and downs. The xb31's fast start-up time of 37 seconds is offset by a poky shutdown time of two minutes. The projector's running temperature of 187 degrees Fahrenheit is pretty hot. The fan is reasonably quiet at 39 decibels.
Our full-motion video tests yielded mixed results. Most DVD sequences ran smoothly with excellent sound synchronization, but the movies looked dark and greenish; in addition, some long pans produced jerky motion. The light leakage from the xb31's side and front also detracts from movie watching.

CNET Labs brightness tests  (Measured in ANSI lumens)
Mitsubishi XD50U
Dell 3200MP
HP xb31
Gateway Projector 210
Optoma EzPro 737
HP's two-year warranty for the xb31 is average for the industry. The lamp is guaranteed for 90 days. If the unit breaks during the first year, HP provides free overnight service and expedites repair, but it does not offer an immediate exchange service, as does Dell.
The 38-page manual comes on CD and adequately covers the features and the operation. HP seems to have gone to significant effort to make the documentation clear and easy to read; nevertheless, the fact that it covers two projectors--the xb31 and the similar sb21--makes some pages confusing.
HP's Web site provides downloadable manuals, maintenance advice, and detailed specifications on the xb31. You'll also find FAQs and troubleshooting tips. Support staff is available 24/7 for e-mail queries or phone questions on the company's toll-free line; when we called, we had to wait 10 minutes before we could speak to someone.

HP xb31

Score Breakdown

Design 8Features 8Performance 7Support 7