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Review: We take Gateway's biggest LCD TV for a spin and see how it handles.

It doesn't take a PhD to know that HDTVs are hot right now. Riding this monster wave, companies like Gateway, HP, and Dell, have all gotten into the HD-capable display business. Gateway's rep is based upon building solid PCs (and a marketing fixation with a certain barnyard animal). What does it know about making a great high-definition screen? That's the question we seek to answer today.

Gateway has brought out an expansive line of both plasma and LCD HD displays. The top of the line is the 30-inch, HD-Ready LCD TV Display, which checks in at just under $3,000. With this offering, the company delivers a compact form factor (only 7.5" deep) and lots of input options. But is its image quality performance up to snuff? Turn the page to find out.

Spec Data:

Here's the quick run-down of the LCD TV's vital statistics:

Product Gateway LCD TV Display Diagonal Screen Measurement: 30" Panel Size 36 lbs. Dimensions (HxWxD) 21.2"x28.9"x7.5" Native Pixel Resolution 1280x768 Supported TV resolutions 480i, 480p, 720p, 1080i through YPbPr, Aspect Ratio 16:9 Panel Response Time 25ms (can run at about 40fps) Viewing Angles (vertical and horizontal) 170° Inputs Faroudja-Enhanced DVD Input, Progressive Component HD Input, Composite, S-Video, DVI, VGA, Audio, PC Audio TV Tuner NTSC (standard-definition) Rated Lamp Life 50,000 hours HDCP-enabled? No

One bit of trickery that vendors sometimes employ is using vague product names. When you see descriptors like "EDTV," "DTV," or "HD-ready," start reading the fine print on the spec sheet. You may find that the display is not a true HD-resolution display. For more on this topic, check out our HDTV primer.

In the case of this particular display, it's described as being HD-ready with a native pixel resolution of 1280x768, so it supports true720p . However, the LCD TV does not arrive with an ATSC Off-the-Air (OTA) HDTV tuner and cannot produce HDTV images by itself. You'll need either a tuner box from your cable/satellite provider or another source for your HD content. The LCD TV can also handle an incoming 1080i HDTV signal, though here it's using a scaler to display the image, since the panel lacks sufficient pixels to handle the 1920-pixel wide format.

We first described our HDTV test methodology in an article about our new HDTV Test Lab

We test via the DVI input of the unit under test at its native pixel resolution, using Milori's ColorFacts measurement software with a Minolta CA-210 colorimeter. The CA-210 is lined up to be perpendicular to the display and positioned at point-blank range.

We test four major areas of display performance:

Contrast ratio RGB color response Grayscale linearity Color temperature linearity

Contrast ratio is the difference between the lightest and darkest values in two test images, one pure black and the other pure white. A large contrast ratio indicates that the display is capable of displaying color subtleties and a very high degree of detail. Contrast ratio can be thought of as a kind of "dynamic range" of a display device. Contrast ratio is an important metric, but can end up being an incomplete indicator of a display's overall performance. For instance, if a display can get very bright, but doesn't get especially dark, the ratio can wind up masking this fact. For this reason, we look at a series of other tests – both objective and subjective – to more fully measure a given display.

For contrast ratio, we take five measurements, one dead-center and one at each of the display's four corners. For the other three measurements, we take one measurement at dead-center.

We measure grayscale linearity to see how close the display comes to 6500 degrees Kelvin along the full IRE range. IRE is an arbitrary unit for gray level, which is really the amplitude of the voltage representing the gray level. 100 IRE is pure white, while the video blanking level is 0 IRE. One IRE unit is 7.14 millivolts.

Next we run 720p HD video material into the LCD TV using a Sencore VP920 HD video player to gauge its ability to display fast-action and color-rich HDTV content. We use the player's VGA connector and run content into the panel under test at 480p, 720p and 1080i.

Using a combination of a Sencore VP403 test pattern generator and a PC equipped with a Radeon 9800 Pro graphics card, we can generate a variety of clean, robust test patterns, such as SMPTE bars, pure red, blue and green, checkerboard, grayscale gradient, and high-frequency patterns to assess image fidelity. We run these test patterns at all HDTV resolutions (480p, 720p, 1080i, and 1080p). Interestingly, the VP403 uses a subset of the DisplayMate test patterns in its firmware.

Finally, we use DVD movie content coming from a Yamaha DVD-S2300MK2 progressive-scan DVD player connected via the panel's component video connectors. Currently we do this testing using the Lord of the Rings: The Two Towers DVD, using both bright, intense action sequences and darker scenes to gauge dark-tone response. Dark tone response is especially important for a display because we perceive light the same way we perceive sound: logarithmically. This means our eyes are very good at distinguishing subtle changes in luminance values in dark scenes, but as we move toward brighter images, our sensitivity diminishes and almost everything appears to be bright to our eyes.

The average contrast ratio from the five measurement points was 518:1, which is quite good. Another important point is that the contrast ratio was consistent across five measurement points, where the highest measured contrast ratio was7% higher than the lowest. However, as previously mentioned, contrast ratio can be somewhat misleading, since it can mask either low bright values or high dark values, neither of which you want to see. With Gateway LCD TV, we have a case of the latter.

Dark values consistently stayed around 0.92 candelas/square meter (cd/m2). We tried three different brightness/contrast and color settings to get this value to go darker, but were unable to get it down below 0.92cd/m2. We tried using the panel's default 6500K color temperature setting, then tried its 9300K setting, and finally manually tweaked color values to try and lower the dark luminance level. So while the bright values of our contrast ratio measurement were nice and bright, the dark values weren't as dark as we would have hoped. The upside is that the LCD TV maintains its image quality in a lighted viewing environment, so you don't need a light-controlled room to use it. The downside, as we'll see in a bit is that detail gets lost in dark DVD movie scenes.

RGB Color Response

The black triangle represents a "perfect" response, whereas the white triangle represents the measured color response. As you can see, the LCD TV does well with red, however, its green response is off somewhat and it failed to deliver deeper blue tones.

Grayscale Linearity

The above graph shows (from left to right) grayscale tracking from gray levels IRE 0 (video blanking level/absolute black) through IRE 100 (full-on white). An ideal plot will be a straight line that runs along the dotted line, which is the target color temperature. The LCD TV's dark-tone levels were above target for the 6500K color temperature, all the way up to 90 IRE, at which point, the LCD TV is delivering the correct luminance level for the target 6500K color temperature. This would seem to indicate that the panel was calibrated using IRE 100 (full-on white) only and not for darker IRE values. We tried dialing down the black level using a variety of brightness/contrast and color temperature settings, but were unable to improve the panel's grayscale tracking performance. These test results correlated well with what we found in our subjective inspection tests.

Color Temperature Linearity

This chart shows color tracking as the luminance level is raised from 0 IRE to 100 IRE, and indicates how uniformly the display device tracks the selected the 6500K target white point. An ideal plot will show all three lines in this graph (Red, Green, and Blue) hovering around the 100% reference line, indicating the display device is converging on or near the selected target white point.

As you can see the LCD TV's color response is off. While green tracks very well, both red and blue are off--and no amount of menu twiddling we did could bring this color tracking closer to being on target. The result might seem initially odd given our RGB color response that showed correct response for red, while green was slightly off and blue was a good bit off. However the RGB color response measurement does not factor in the luminance value for the color responses, only the level of color saturation. However when we compare the RGB tracking measurement with the grayscale linearity measurement, we see good correlation between the panel finally hitting the target white value (6500K) and the RGB levels converging at around 80-90 IRE.

Our visual inspection tests aligned pretty well with our measured objective test results. Generally speaking, the panel worked well in a lit room, thanks to its bright white values. However, dark tone detail was often found wanting in images both from the VP920 HD video player and our Yamaha progressive-scan DVD player. We tested using both the HDTV input and the LCD TV's Faroudja-enhanced DVD input.

In scenes from Lord of the Rings: The Two Towers entire details in darker scenes from were simply not visible. Again, we tried to tweak contrast and brightness values to correct this issue. We were able to recover some of the scene detail, but in doing so, black levels started to become washed out. We also observed some banding in very bright scenes. Video playback quality is one area where LCD panels still often trail plasma displays and Gateway's LCD TV didn't handle this content well.

Next we ran 720p HD content into the LCD TV to gauge its ability to display HDTV content. While color saturation looked fine, we again found that the dark levels were not really dark enough and that there was a certain amount of wash-out.

When we tried to dial down the brightness level, we made an odd discovery. The brightness and contrast controls operate on a 100-point scale, but the brightness control had no effect on the display's black level until we dialed it up past 65. At this point, the overall brightness increased and, as we expected, black levels began to get washed out. So the LCD TV's brightness control effectively only operates on a 35-point scale. We dialed the black level down further and our CA-210 colorimeter confirmed what our eyes were seeing.

Weighing in at 36 pounds, the LCD TV was easy to move around and get positioned in our test space, and its 52-page indexed manual made setup a breeze. This particular model comes with an optional pair of speakers that hang on either side of the display. Our review unit didn't arrive with the speakers, but generally speaking, we're not fans of onboard speaker systems in displays. Between bill-of-material costs and shielding issues, these audio systems almost always disappoint, and audio chores are best left to more robust, dedicated audio gear.

The LCD TV comes with a large universal remote control whose buttons light up when pressed, making navigation in a dimmed lighting environment easier. However, text for the input selector buttons is on the remote itself, and while the buttons light up, the text does not. So, selecting the right input in a dark room ends up being like trying to read Braille. The remote can drive seven other devices in addition to the LCD TV. We did notice early on that the LCD TV's IR receiver for the remote wouldn't receive commands if the remote was at much of an angle.

The LCD TV's onscreen display (OSD) menus are easy to navigate--almost all the controls are straightforward and intuitive. The default color temperature is 6500K (also known as D65) and while the display supports 9300K, that setting takes on a decidedly blue hue. We poked around in all the menus and scoured the documentation, however the LCD TV does not have an obviously accessible service menu that allows deeper, more granular tweaking of the panel's settings.

The LCD features three different dual-display modes: picture-in-picture, picture-on-picture and picture-by-picture. These features work as advertised and the menu options allow you to quickly swap the positions of the two feeds. However, turning these features on or off requires drilling into the menus every time you want to use them. What would make the feature more useful would be to have a single PIP/POP/PBP on/off button on the remote control to allow it to be quickly enabled or disabled.

While the LCD TV's video performance disappointed us, we were impressed by how well it worked as a PC display. It has plenty of input options and its form-factor makes it easy to tuck into fairly small areas or even hang on a wall. That said, this isn't a display we can recommend to you. Even if you were going to use it as dedicated PC display device, its 25ms response time can only effectively draw 40fps, so ghosting in 3D games is highly likely.

In the coming weeks, we'll be reviewing Gateway's 42" plasma screen, which also carries a $3,000 price-tag. If its video performance is up to snuff, that--along with 40% larger diagonal screen size--might garner a better recommendation from us. But the LCD TV, given its video performance shortcomings, is not what you're going to want at the heart of your entertainment center.

Note that Gateway recently offered the LCD TV at a sale price of $1,999. At that price, it gets a little more interesting, but it's still not an ideal candidate for movie buffs, or anyone who wants better dark scene detail.

Product Gateway 30-inch HD-Ready LCD TV Display Web Site: www.gateway.com Pros: Thin and light; good contrast ratio; works very well as a PC display; plenty of input options Cons: Expensive; TV tuner is standard-definition (not HD); poor dark tones response Summary: As a display that will pull double-duty as a PC monitor and a movie screen, the 30" LCD HDTV from Gateway does a fairly good job. But its response time makes it less than ideal for gaming and as a pure video device, its dark tone performance leaves something to be desired. Price: $2999.99 Score:

Copyright © 2004 Ziff Davis Media Inc. All Rights Reserved. Originally appearing in ExtremeTech.

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