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A view to a kill
The Viewsonic VX924 comes from a long line of high quality LCD screens. This unit however is something that every gamer should consider. Why? Not only because it is a 19 unit but it sports a response time of just 3ms.

Suddenly LCD monitors are everywhere, but as with most growth areas the range in quality from one model to another can be vast. Making matters worse is that you can't even rely on the quoted specifications to give any kind of an indication about the quality you'll get.

Most potential buyers tend to concentrate on just three parameters when researching LCD monitors, its brightness, contrast and response times. In general the first two are as good as worthless because while they may tell you what the display is capable of, they don't tell you if it's usable. Contrast can be achieved by increasing the brightness of backlight but on a screen with poor blacks this will do nothing to improve them. At best it will lead to a display that's better suited to more brightly lit environments. What's needed is an industry standard brightness level at which contrast ratios are calculated as this would at least make it easier to compare one model with another.

One specification that has been given a lot of consideration and rightly so, is response time. This is the time it takes for a monitor to light then extinguish or to change the shade of, a single point of light known as a pixel and this where CRTs have a very definite edge. A CRT monitor can switch its pixels in nanoseconds whereas until recently, LCD monitors were actually very inefficient at switching their pixels, particularly when changing shade rather than switching from full on to full off or vice versa. The effect of this inefficiency is that a new frame is displayed while the previous frame(s) is still fading, not a problem on a static image but a recipe for blurring and ghosting on faster moving images, just the type that are often found in games and videos.

I don't want to get too involved in the technicalities behind response times but in order to understand how Viewsonic have achieved such a low response time we need to understand a couple of basic principles.

Try to imagine an LCD cell as a bunch of rod shaped crystals trapped between two pieces of glass and held in a thick liquid suspension. Applying a voltage to selected areas of the cell causes the crystals to rotate and the actual shade is controlled by how far they rotate, which in return is proportional to the amount of voltage used. Causing a full rotation is fairly efficient because the relatively high voltage gives the crystals a good "kick", but getting them to rotate by say, 10%, means a very low voltage is used and the crystal responds much more slowly.

ViewSonic use three essential tricks to improve response times. The first is they decrease the viscosity of the LCD suspension material meaning the crystals find it easier to rotate. Next they reduce the cell gap, the distance between the front and rear glass panels, which reduce the amount of material between them and thus allow the crystals to operate without interfering with each other. The final trick is what ViewSonic call "Amplified Impulse Driving". This involves applying full voltage to the cell to get the crystals moving and then reducing it to the required level once they're in motion. These combined technologies have been called "ClearMotiv" and should allow framerates suitable for just about any gaming or video situation.

Click to enlargeThe monitor I'm reviewing today is the ViewSonic VX924, a 19" screen that, though initially rated at 4ms, was later reclassified as a 3ms display after more thorough testing at the ViewSonic labs. This means, in theory at least, that this monitor should be good to over 300 frames per second, or in short, a space-limited gamers' wet dream.

In styling terms the VX924 is sleek and simple if a little unspectacular. Primarily black in colour it has a silver accent around the outside edge of the screen bezel extending down behind the control buttons. The overall quality is good despite the heavy use of plastics and it certainly feels capable of handling the daily rigours of regular use.

Compared to some of the slim line monitors on the market the VX924 is comparatively deep, but this is forgivable because it actually houses its voltage transformer within the body of the monitor rather than as a separate external unit as is more common for this price. In fact considering the integral transformer it's commendably compact. Most monitors look fairly dull from the back but ViewSonic have cleverly added a silver logo that both adds a little style and performs a little advertising at the simultaneously.

There are five main control buttons on the lower edge of the screen. These are large and easy to use though the labels beneath them tend to get obscured with the monitor on a desk. On a monitor shelf they're easily seen, but this leads to a quite separate problem in that there seems to be almost no forward tilt available and I found I had to prop the rear of the stand on something to set a suitable viewing angle.

The five control buttons allow access to the various menu options which include an auto-adjust function (analogue mode only), contrast, brightness, input select (D-sub analogue or DVI digital), colour temperature (sRGB, 9300, 6500, 5400 and user defines), display information, manual image adjustment including a fine tune (focus) adjustment for use in analogue mode, setup for OSD position, language, OSD timeout, OSD background and resolution notice and finally a memory recall function.

Both D-Sub (analogue) and DVI (digital) inputs are catered for. The VX924 comes with no integral speakers which isn't a great loss for most people.

Incorporated into the base is a rather useful cable management system. This is all the more important thanks to the integral power transformer which of course means that instead of a slim, low voltage cable feeding it you have the normal, thick, 3-core power cable plugged in at the back.

The black panel on the base stem flips off revealing a pair of cable retainers which feed the cables down to the bottom of the stand.

So how does the Viewsonic VX924 stack up in testing? Find out on the next page.
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