With PC makers like Dell and HP dipping their toes in the HDTV waters, it should come as no surprise that PC display makers have decided to get their feet wet as well. ViewSonic, a longtime maker of PC monitors, has brought several HDTVs to market based on LCD and plasma-panel technologies, with 13 different models currently on the market. The company's 42-inch, HD-ready VPW4255 plasma panel is a decent performer, though not without a few warts.

The VPW4255 seems to emphasize function over form. Its stand and bezel are pleasant enough to look at, but the relative lack of input options, minimal remote, and rudimentary on-screen controls don't seem in line with a home-focused HDTV. The unit has two component video inputs and a SCART input (for Europe). It also has a VGA port and a DVI/HDCP port to accept a digital video input from your satellite/cable box. If your digital set-top box uses HDMI, you'll need an HDMI-to-DVI adapter.

The panel itself has a native pixel resolution of 1,024 by 1,024 and has nonsquare pixels, which allows it to have a 16:9 widescreen aspect ratio. As such, this is not a true high-definition display. There has been a great deal of confusion about what constitutes true HD. At a minimum, an HDTV should have at least enough pixels to display 1,280-by-720, the native pixel resolution of 720p. Because of its configuration, the VPW4255 uses a video scaler for both 720p and 1080i HDTV content, and the panel's video processor turns out to be its problem area.

On subjective tests, the VPW4255 posted some respectable numbers for a plasma panel, exhibiting good (but not great) contrast ratio and black levels. But we noticed visual artifacts such as small amounts of green "noise" in what were supposed to be purely black areas. This noise was also visible on other test patterns that included dark gray tones.

When we switched over to other video sources, such as Voom HDTV and DVD movies, we noticed that this noise persisted in the dark and black areas of the screen. Worse, we noticed considerable dithering in areas where colors were gradually ramping. At a distance, this dithering became less noticeable, but it was still visible. And sometimes we saw slightly amplified noise (compression artifacts) in some of our test content. Again, at a typical viewing distance of 6 to 8 feet, such problem areas were less visible, but we could still see them. In addition, static text, such as a score box in a sports broadcast, was jittery: The static text/graphics would seem to vibrate up and down. This indicated that the video processor wasn't able to keep this part of the image steady—a problem that will eventually cause some viewing fatigue.

All told, we found the VPW4255's overall video performance wanting. On our video tests, we came across just too many issues to ignore. It might be fine for a kiosk application, but look elsewhere for a plasma panel for the home.

Benchmark Tests
Average contrast ratio (higher is better): 224:1
Average dark level (lower is better): 0.6 cd/m2
Average bright level (higher is better): 130.4 cd/m2
White uniformity (VESA) (higher is better): 95.3%
Black uniformity (VESA) (higher is better): 80.6%