Iiyama AS4431D

So it's time to lay that old CRT to rest and, of course, a TFT larger than 15in would be nice. But you end up paying an extra £1,000 for three more inches. Whatever your priorities are, this is a serious consideration, one where the saving per fraction of an inch is well worth having. Taxan, with its Crystalvision 780 TCO99 (reviewed below), and Iiyama have opted for a 17.4in compromise this issue, although the Iiyama costs over £200 more.

Iiyama's AS4431D gets off to a good start with its well-conceived design - a single unit, with no external power supply and no fiddly rear input covers. All the inputs are instead arranged down the right-hand side, with non-captive D-SUB, DVI, composite and S-Video connectors and a four-port USB hub on the base, with an upstream port to the PC at the back. There's also a pair of stereo speakers built into the base, which saves space.

It's worth using the DVI input if your graphics card supports it, as the difference in image quality is outstanding. The Iiyama reproduced all the DisplayMate resolution tests faultlessly, and the colour registration tests were also performed admirably. The only problem with the DVI input was an occasional graphical glitch that flashed across, particularly on black screens. These were minimal with the ATi All-in-Wonder Radeon (reviewed issue 76, p160), but became much more noticeable on nVIDIA-based cards.

These problems disappear if you switch to the analog input, selectable through the OSD. However, this results in a substantial drop in image quality and the display looks dull in comparison. The resolution tests also fared less well and it was impossible to get the clock and phase settings spot on without interference, even using the automatic setup option. Colour temperature can also be adjusted, although the lack of separate RGB controls limits its use.

Downscaling at lower resolutions was handled well enough, although not as smoothly as high-end TFTs like the Eizo FlexScan L771 (reviewed issue 75, p179). The best results come from the native 1,280 x 1,024 resolution, which is just right with the 17.4in diagonal.

The only criticism with the panel is an odd bowing effect across the top. This would seem impossible given the nature of TFTs, but the top edge dips slightly, making the corners look like they're stretching outwards. When looked at head on, the AS4431D retains pure colours and even brightness. However, viewing angles weren't outstanding and this makes optimal positioning quite difficult. One useful feature is that the panel can be rotated, using the supplied Pivot software, to give you enough space for a portrait sheet of A4 in actual size.

Iiyama will have to do some fine-tuning to make this worth the money. The DVI picture is sharp and clear, but the graphical glitches are annoying and it's difficult to justify the extra £300 over the Taxan with a few extra inputs. When these issues are ironed out, it will be worth having for the DVI picture quality. If your graphics card doesn't support it though, you'd be better off with the cheaper Taxan.

Author: Ben Hardwidge