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How We Tested

When evaluating monitors a controlled environment is essential to ensure that consistent and repeatable results are obtained. For this group test, our main test bed consisted of a single PC, fitted with a 32MB (DDR) Matrox Millennium G550 Dual-DVI graphics card with a RAMDAC of 360MHz. This card is capable of simultaneously running two analogue (D-SUB) monitors or two digital (DVI) monitors. However, at the time of writing, this card was not capable of running two monitors at a resolution of 1,600 x 1,200 and thus, in every case, its dual-head function was disabled.

Each monitor was tested with only one connection at a time using the cables supplied by the manufacturer. All monitors were positioned in the same orientation on our purpose-built test bench, separated by at least one metre from other equipment in order to minimise any interference. In addition, the monitors were left to warm up before assessment under controlled lighting conditions. Before analysis we also installed the appropriate drivers supplied by the manufacturers.

As well as the test bed, all the units were used every day for a period of at least two weeks on our own systems. This allowed us to truly become familiar with the performance, usability, aesthetics and build quality of each display.

DisplayMate for Windows Tests

All TFT flat panel tests were carried out at the native resolution of 1,600 x 1,200 at 60Hz, with a 32bit colour depth. Each unit was also set to its default colour temperature, and the contrast and brightness adjusted for optimised greyscale reproduction. However, as DisplayMate is geared towards testing CRTs, only a selection of its tests were employed. From those already described, the following are considered most appropriate. Text focus, colour scales and greyscales, colour purity and background interference.

If the flat panels were fitted with an analogue D-SUB port we also checked and adjusted the pixel phase and clock using DisplayMate’s pixel-tracking and timing-lock test screen. If digital noise persisted it was noted. Our final technical test involved assessing the viewing angles and comparing them with those stated by the manufacturer. If these were much less than stated the scores were lowered, whereas units that demonstrated particularly impressive angles, both horizontally and vertically, gained higher ratings.

In addition, each flat panel was tested using real world scenarios. First, we looked at how well photographic images were rendered, paying specific attention to flesh tones and large areas of colour that exhibited slight variations in tone. We also assessed the colour, brightness, contrast and detail during DVD movie playback, while also looking out for signs that response time was contributing to lag and motion smearing.

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