Buying Guide: Best monitor: 12 LCD screens tested

Picking where to put your pennies when it comes to pricing up a PC can be a pain. Buying the best of everything would sidestep the problem neatly enough. In reality, lottery winnings and banker's bonuses are hard to come by.

Compromises must be made. But if any component deserves a large chunk of your dosh, it's undoubtedly a flat panel.

For starters, the screen is quite literally a window into the workings of your PC. It's the one component that influences the user experience every time you sit down and fire up. Put another way, a shader-packed graphics card is great for games. For everything else, it's a billion transistors twiddling their thumbs.

A high-end CPU admittedly has a wider repertoire. For most things, most of the time, however, a cheap quad-core chip delivers all the performance you can actually use.

So, a good PC monitor gives more and it gives it more often. That's not all. Flat panels do not develop as rapidly as most PC-related technologies. Buy a high-end pixel pumper today, and it will be looking old hat inside six months; Performance boosts of 50 per cent or more from one generation to the next isn't unheard of. Likewise, CPUs, hard drives, you name it. But not screens.

A great example here is our very own Dell 30 incher. It's over three years old. That's an eternity by the standards of most PC components. But it's still a stunning screen. In terms of scale and resolution, in fact, it hasn't been bettered.

What's more, it probably has at least a year or two as a high-end screen left in it. In that context, if you'd paid £800 in 2007 you can spread the cost over five years. Suddenly, it doesn't look so expensive.

That's not to say flat panel technology is at a stand still. As we'll see, there are some interesting developments afoot in all parts of the market. But what it does mean is that is that a quality monitor is almost definitely the best long-term investment that you can make for your PC. With the general case in favour of flat panels all sown up, it's time to get specific.

The PC monitor industry is currently dominated by a single screen technology, the liquid crystal display or LCD for short. However, there are several variations on that theme. Not all panels are equal.

LCD panels explained

Getting to grips with the three main LCD panel types is therefore your first and most important step towards flat-panel perfection. However, it's also handy to have a basic understanding of how an LCD panel works. Every picture element or 'pixel' in a liquid crystal display contains – you guessed it – liquid crystals.

A typical LCD panel is made up of thousands, if not millions of these pixels arranged in a grid. Behind this grid is a backlight. Shove an electric current through the crystals courtesy of a pair of transparent electrodes and – presto-chango – they realign.

In simple terms, there are two basic positions or states the crystals can assume, one that blocks light and one that allows light through. Strictly speaking the crystals don't actually block light, they polarise it and in combination with static polarisation filters light either passes through the LCD panel or is blocked.

Anyway, the crystals can assume a huge number of intermediate positions between on and off, allowing some but not all light to pass through. What's more, in a colour LCD panel every pixel is made up of three individual elements covered by filters in the primary colours: red, green and blue. Vary the intensity of light passing through each of these elements and you end up with a full palette of per-pixel colours. Clever, eh?

If that's the basics, the details of how each panel controls the crystals vary considerably and that throws up some very obvious differences in image quality. Which brings us to the first of our flat panel triumvirate: cheap 'n' cheerful Twisted Nematic. Usually known as TN, its raison d'etre is quite simply to be the most affordable full-colour active-matrix LCD technology.

Consequently, TN panels aren't exactly renown for world-beating visual fidelity. The trouble with TN In fact, TN panels suffer from a number of inherent image quality problems. Poor viewing angles are perhaps the most obvious give away that you're looking at a TN panel.

The problem here involves the way the liquid crystals in a TN panel are effectively fixed at one end. When a current is passed through, the crystals bend or 'twist', hence the name. However, this is not as effective or accurate as crystals that are free to fully rotate.

The upshot of using this particular technology is that light tends to leak out at undesirable angles and that means that colours can look odd if the panel is not viewed from directly in front of it. Then there's the fact that the default position of the crystals in a TN panel allows light through. Combined with the restricted crystal movement, this tends to result in poor black colours, limited contrast and an overall watery, washed out appearance. Put simply, TN panels are leaky when it comes to light.

Those bendy crystals make for relatively poor colour accuracy, too. However, it's not all bad news. The limited range of crystal movement does have one upside – quick response. Put a current through a TN pixel and the crystals jump to faster than any other panel type. That means sharper moving images. Perfect for games and films, in other words.

In-Plane Switching

Next up is In-Plane Switching or IPS. This technology is effectively everything that TN is not. In other words, it's pricey but pulchritudinous [Ed - the dictionary says 'bootiful!'].

For starters, the crystals in an IPS panel are free to fully rotate about their axis. They also have a pair of controller transistors per picture sub-element where other panel types have just one. The net result of which is that IPS panels control light better than any other LCD technology. That translates into the most accurate and realistic colours and the widest viewing angles. And that's why you find companies, such as Apple trumpeting the use of IPS panels in devices like the iPhone 4.

In many ways, IPS is the finest LCD tech available at the moment. IPS is not, however, the best by every metric. The extended range of movement the crystals can achieve makes for longer response times and blurrier moving images. IPS panels are also not all that hot at completely blocking out the backlight.

VA, the halfway house

Indeed, that's a trick done best by our final panel tech, Vertical Alignment. There are two types of VA panels, PVA and MVA. The former is more common, but the basic principles are common to both of them.

Most significantly, the default, current-free position of the crystals blocks light from passing through. This allows the deepest and most convincing blacks of any LCD panel technology and the greatest contrast between dark and light tones. That in turn allows for the richest, most saturated (if not the most accurate) colours.

In most other regards, VA panels are a perfect halfway house between TN and IPS panels. They're more colour-accurate than the former, but lack the fidelity of the latter. Likewise, VA screens are halfway between the two when it comes to viewing angles and pixel response.

Screen tricks

If that's the crucial panel types covered, there are a number of secondary screen technologies that are worth understanding. Until recently, backlight technology had been essentially static for a decade or more. You could have any backlight you wanted, as long as it was based on Cold Cathode Fluorescent Lamps (CCFL).

More recently, LED or Light Emitting Diode technology has begun to assimilate LCD monitors, having already become de rigueur in high-end HDTV sets. It's important to appreciate that current LED monitors are still based on LCD technology for the panel itself. It's only the backlight that is LED powered.

All the usual LCD caveats therefore apply. However, LED backlights do deliver a number of important advantages.

For starters, they use less power. They also respond more quickly, making dynamic contrast technology more viable. But most of all, they produce purer light, allowing a wider gamut of colours.

Another factor that effects image quality on any monitor is digital image processing technology. At least, that's what the manufacturers would like you to believe. The most widely publicised is dynamic contrast. The theory behind dynamic contrast makes a lot of sense.

Games and movies vary in brightness from outdoor daytime vistas to dingy dungeon scenes. Why not vary the backlight to suit? That's just what a lot of monitors are now capable of doing. The result, on paper at least, are incredible contrast ratios measuring in the millions to one.

In practice, dynamic contrast doesn't really deliver. More than anything, it tends to crush detail in darker scenes.

Another lesser known digital enhancement technology is pixel overdrive. The idea here is to improve pixel response. It's achieved by pumping excess voltage through the liquid crystal in an attempt to get them to move more quickly. In practice, it does just that. But it also has a tendency to cause the pixels to overshoot the target colour state. When that happens, the colours can go a bit, well, weird.

That's not all. When used in VA panels, overdrive can cause another problem, the dreaded input lag. This involves a tangible delay between the output signal from the video card and the resulting image update on the panel itself. As an end user, you notice this in the form of sluggish mouse responses on the Windows desktop or laggy inputs when playing games.

Pick a panel (or two)

That's key technologies covered. Now it's time to pick a panel and that means setting a budget, choosing a size and deciding on the resolution. When it comes to the latter, your choices have become more limited of late.

Nearly all 22 to 24-inch panels now sport the standard full-HD 1,920 x 1,080 resolution. On the upside, that means that even bargain basement 22-inch panels below £150 offer as much desktop real estate as many larger screens. In fact, you have to go all the way up to the likes of Dell's £700-plus U2711 27-inch monitor or HP's £1,200 30 incher before you actually get more pixels than a cheap HD 22-inch monitor.

It's also worth remembering that the pixel pitch, or pixel size, on a 22-inch HD monitor is much smaller than that of a 24-inch or larger HD monitor. That impacts image quality in a number of mostly positive ways such as improved clarity and sharpness.

A more ambiguous benefit of a tighter pixel pitch is smaller text, which will or won't bother you depending on your eyesight. A further knock-on effect is that with 22-inch HD monitors, the pixel pitch is so small it's debatable whether anti-aliasing is really necessary.

So, there you have it. It may seem like there's a lot to learn when it comes to picking a panel. But the key lessons are simple enough. First, remember that all panels are not equal. If a given screen is large and cheap, it's probably based on a TN LCD. Second, the latest LED powered monitors are desirable but not the huge leap forward manufacturers would have you believe. Finally, don't assume that a bigger screen will have a higher resolution, that's rarely the case.

Hit the next page for the monitor reviews...

HANNS.G HP222DJ0
£134 22-INCH

When does a cut-price screen becomes a flat-screen false economy? It's tempting to think the Hanns.G HP222DJ0 is plenty cheap but not particularly cheerful. After all, by at least one obvious metric it's well behind the competition.

This is an old school 16:10 aspect ratio screen where the rest of the known universe has gone 16:9. The old-school means full 1080p HD is not on the menu here. Instead, you must make do with 1,680 x 1,050.

LG E2350V
£149 23-INCH

A 23-inch monitor with a full-HD 1,920 x 1,080 pixel grid for under £150? Impressive stuff. But that's not all. The brandspanking LG E2350V adds a voguish LED backlight to what already seems like a bonkers bargain.

Then there's the screen bezel hewn from transparent purple plastic and sporting a glossy finish, not to mention HDMI and DVI connectivity. It's a great package.

IIYAMA E2271HDS
£150 22-INCH

When it comes to screens, bigger isn't always better. At least, that's the hope for the new Iiyama E2271HDS. By most metrics it looks competitive with the £150 monitor brigade.

But at 22 inches in overall screen girth, it's a little short on stature. While the E2271HDS might be smaller than some of the competition, it's still a full-HD panel, packs 1,920 x 1,080 pixels and sports an LED backlight.

BENQ EW2420
£158 24-INCH

This is it, folks. The holy grail of LCD monitors. The messiah of flat panels. A truly affordable large display powered by something other than a TN panel, in other words. We give you the new BenQ EW2420 24 incher, yours for a whisker over £150 and sporting a VA panel. Cue much rejoicing.

That's cheaper than many 24-inch TN monitors. But somehow the EW2420 also packs an LED backlight and delivers the real-HD deal courtesy of a 1,920 x 1,080 pixel grid.

BENQ V2410T
£162 24-INCH

Spare a thought for the BenQ V2410T. Until recently, it was an extremely attractive 24-inch monitor. Not only does it sport a full-HD 1,920 x 1,080 pixel grid. It also packs an LED backlight and a fully adjustable stand.

Not bad for around £160. Problem is, BenQ itself has only gone and launched the even more desirable EW2420, taking the 24-inch plus LED recipe and adding VA panel technology to the mix.

SAMSUNG LD220Z
£225 22-INCH

Got a desktop replacement laptop and fancy adding a second display in dual-monitor mode? Then the Samsung LD220Z Lapfit Touch is for you. It's a 22-inch full HD screen designed for portable PCs. As the name suggests, this has full multi-touch functionality.

In fact, it doesn't even need special drivers. Connect via USB to any Windows 7 PC and the touch capabilities are enabled. Ergonomically, it works well enough and it's a slick-looking screen thanks to the minimalist design and glossy black bezel.

IIYAMA E2710HDS
£235 27-INCH

When it comes to sheer visual drama, there's no substitute for square inches. You need a really large display like the Iiyama E2710HDS. What you do not need, however, is a banker's bonus to afford one. An impressive 27 inches of flat panel is now available for under £250.

Still, it's no surprise to find the Iiyama E2710HDS gives you little extra apart from those inches. The panel technology is, of course, trusty old TN and the native resolution is 1,920 x 1,080 pixels.

SAMSUNG PX2370
£238 23-INCH

Desktop monitors with cheap TN panels have been the bane of our computing lives in recent times. But what about desktop monitors with expensive TN panels?

Enter the Samsung PX2370: a paradox in a flat panel. Without doubt, TN screen technology has improved dramatically in the last 18 months. But can this 23-inch TN panel justify its hefty price tag?

HANNS.G HZ281
£279 28-INCH

There can be only one winner in the battle of the big, budget-priced screens. But will it be this 28-inch Hanns.G HZ281 monitor or its nemesis, the 27-inch Iiyama E2710HDS?

The 28-inch Hanns.G obviously squeaks it for square inches. However, the HZ281 also sports a 16:10 aspect ratio. That makes the size differential in square inches even larger. But it also means the HZ281 has more pixels.

ACER GD245HQ
£289 24-INCH

Whether it's gaming or movies, it seems the whole world is going mad for stereoscopic 3D. Does that make the 3D-capable Acer GD245HQ the monitor of the moment?

By most metrics, it's a pretty ordinary panel. It's a 24 incher with a TN panel, a CCFL backlight and the standard issue 1,920 x 1,080 HD pixel grid. None of that would be bad if it weren't for the near £300 pricing.

DELL U2711
£766 27-INCH

Can PC monitors be too big? Speak to owners of über 30-inch displays and you may be surprised by the answer. That's where the Dell Ultrasharp U2711 steps in.

At 27 inches, it's significantly smaller than ultra-panels such as HP's ZR30W. But thanks to a monster pixel grid of 2,560 x 1,440, it gives very little away in terms of native resolution. It's also quite a bit cheaper than most 30 inchers. But you still get a first-rate feature set.

HP ZR30W
£1,189 30-INCH

Think about computing giant HP and we suspect images of corporate cubes leap to mind more readily than sexy screens. But there's no doubting the new HP ZR30W is an absolute stunner.

It's a 30-inch monster with a high quality IPS panel and a monster resolution of 2,560 x 1,600. It comes with a massive price tag to match, of course. But the HP ZR30W is an awful lot of screen.

And the best monitor is...

The market for vaguely affordable LCD monitors has been dominated by mediocre TN panels with samey image quality for some time now. Mercifully, that has finally begun to change.

Firstly, BenQ has blown things wide open with it's ridiculously cheap new 24-inch VA screen. Here's hoping that becomes a trend. Even if it's a one off, however, there are reasons to be optimistic.

The rapid adoption of LED backlights is giving a welcome boost to image quality across almost all price points. Moreover, panel manufacturers are beginning to get to grips with the inherent shortcomings of TN technology. The best TN panels of today aren't far off matching IPS panels from a few years ago.

On that optimistic note, it's time to wheel out the prizes. Bringing up the rear is Hanns.G's 22 incher, the HP222DJ0. In isolation, it's not a bad panel for around £130. But you get so very much more for an extra £20 in terms of everything from size to resolution and image quality.

Next up is Samsung's PX2370. It's a surprisingly poor showing, but there's no getting around the fact that this 23-inch monitor is horribly, horribly overpriced.

Another Samsung display takes the next slot. It's also overpriced, but the LD220Z Lapfit Touch does have a number of unique features, including multitouch capability, to justify its £225 tag.

There's absolutely nothing ordinary about HP's majestic 30 incher, the ZR30W. It's a fabulous screen. Problem is, it comes at a fabulous price.

Dell's gorgeous 27-inch U2711 is pretty pricey, too. But £700-odd feels much more attainable than nearly £1,200. In either case, if you can afford them you won't be disappointed. It's going to be literally years before anything significantly better than this pair comes along.

If £700-plus is out of the question, do not despair. A pair of very serviceable large-scale screens is available for a fraction of the cost. The Iiyama E2710HDS is bright, powerful and gives you 27 inches of full HD for just £235.

Even better, if only marginally, is the Hanns.G HZ281. It gives you an extra inch and a few more pixels along with an equally powerful backlight and decent image quality. All of which means there can be only one winning panel.

You might think it was obvious from the beginning. But the BenQ EW2420 still had to deliver on the enormous promise of a 24-inch VA panel, plus LED backlight for just over £150. It's not a perfect screen, but it's by far the best budget monitor currently on the market.