How to buy a new screen for your PC
With many types of monitor out there at varying sizes and prices, which one is worth the cash?
We've said it before, we're going to damn well say it again, and we're going keep saying it over and over until somebody starts listening.
By far and away and without a shadow of a doubt, the best long term investment you can make for your PC is a decent screen. Repeat, LCD screen.
That's especially true at the top-end of the market, where some specs have stagnated. Back in 2006, the pinnacle of PC screendom was 30 inches and a native resolution of 2,560 x 1,600. Fast forward to the dawn of 2012 and absolutely nothing has changed. That's still as good as it gets.
In fact, if anything, prices of premium panels have hardened. Premium 24-inch monitors based on the better VA and IPS panels are quite possibly more expensive than they were five or six years ago. The problem is the market for higher-priced panels – there isn't one.
People buy almost purely on price; they just want cheap and cheerful. That said, this obsession with cheaper screens means the focus is on squeezing the most out of a sub-£300 budget.
Today, that figure doesn't just secure full HD resolutions and stretch to 27-inch and even 28-inch monitors, it also bags you a multi-function monitor packing everything from an integrated TV tuner to full stereoscopic 3D support using the technology of your choice.
Until recently, what you wouldn't get was anything other than TN technology for the panel, but there are now some exceptions. Along with some affordable VA panels, the new kid on the block is e-IPS tech, which is effectively a cheaper version of the IPS screens favoured for their colour reproduction and found in many premium devices including, yes you guessed it, Apple's iPhone and iPad gadgets.
As for the TN masses, the good news is that the technology continues to improve, closing the gap with IPS and VA. It's also worth noting that the increasingly widespread use of LED backlighting, even at the arse end of the market, has given TN a kick up the backside too.
All of which means there's serious value to be had if you know what you're buying, which is exactly where this month's LCD panelfest comes in.
Every screen purchase should start from a position of informed awareness. You need to know what you're buying and that means getting to grips with the different panel technologies. Yup, we have been here before, but given the lengths some monitor makers go to obscure and obfuscate the underlying technology, it's more critical than ever to know your TNs from your PVAs.
I DREAM OF 3D: If slaying dragons in 3D appeals then look for a screen with 3D support
From the top, the cheapest and most commonly used panel tech is our old friend TN. Otherwise known as 'twisted nematic', in layman's terms the thing that really matters about TN technology is that the liquid crystals in each picture cell are effectively fixed at one end. When an electrical current is applied, the crystals twist rather than rotate.
This explains TN's strengths and its weaknesses. The tension involved in twisting crystals in one direction means they pop back the other way more rapidly. The result? Fast pixel response.
Of course, with one end fixed, you never get the full rotation achieved by other LCD tech, which means light isn't managed as accurately or blocked as fully. Result? Inferior colour accuracy, less expansive viewing angles and poorer contrast.
One of the specific consequences of the restricted crystal articulation is the need for dithering. TN panels can't natively display as many colours as IPS and VA screens. The solution involves forcing pixels to jump rapidly between two colour states in order to fool the human eye into observing a third, incremental colour. In theory, it should be invisible. In practice, it's sometimes possible to see the pixels fizzing away as they hop between colours.
Everything is relative though. Ongoing improvement of TN technology has given us panels superior in some regards to IPS panels of six or seven years ago.
What's more, it's not just the panel technology that has improved. The market-wide shift from CCFL backlights to LED technology has been a big help for TN screens. You get a broader spectrum of light, which helps compensate for the inherently poor colours. So, TN monitors with LED backlights are more vibrant and sock you with more saturated colours. Yay!
Despite all of this, there are limitations to TN, and they can be spotted on the spec sheets. That's true even when the monitor maker doesn't deign to mention the panel type. Unfortunately, that's pretty frequent.
Anyway, the markers you're looking for go something like this. Start with the viewing angles, the metrics manufacturers use vary, but if either figure is under 170°, you're looking at a TN. Typically a vertical angle of 160° really gives the game away.
The other major give away is contrast. The tricky thing here is that dynamic contrast – in other words, contrast achieved by modulating the backlight - is often the only figure quoted. Any figure of roughly 5,000 to one or greater will be the dynamic rating. If it's lower than that, it's likely to be contrast with a static backlight.
THE WINKING SKEEVER: "Skyrim belongs to the Nords!"
Until recently, anything capable of 1,000 to one or more for static contrast was very likely to be VA or IPS. More recently, TN monitors capable of 1,000 to one static contrast have appeared.
At the same time, VA and IPS panels have upped their game. So any quoted figure above 1,000 to one (but below 5,000 to one) will indicate a panel other than TN.
The final give away is price, but here again, things have begun to change. Until recently, VA and IPS panels were always much more expensive. The good news is that lower cost derivatives, including e-IPS and MVA, are becoming ever more common. It's now possible, for instance, to buy a 24-inch MVA screen for under £180. If that's TN, what about the other two?
Our next candidate is 'In-Plane Switching' or IPS technology. It occupies completely the opposite end of the scale from TN for everything from price to colour accuracy.
Critically, where other panel technologies include a single controller transistor per subpixel, IPS packs a pair and offers superior crystal control and, in turn, the best colour accuracy. Of course, increase a product's complexity and you increase costs. But that's not the only downside – the extra transistors also block light. That makes IPS notably less vibrant and saturated than the best VA panels.
Another upside of IPS is extremely wide and consistent viewing angles. Unlike TN crystals with their rooted ends, the liquid crystals in an IPS panel rotate fully about their axis. That matters because it allows them to present a more consistent face to the viewer at varying angles and means a more constant quantity of light passes the red, green and blue subpixels regardless of the viewing angle. In other words, you don't get wonky colours if you sit in an off-centre position at your desk.
There is, however, a snag. That greater range of crystal articulation translates into longer response times when transitioning between extreme colours. The longer that process takes, the blurrier a panel looks when rendering moving images.
That said, just as TN technology is closing the gap for colours and contrast, IPS screens keep getting faster. Factor in the static fidelity advantages and it's easy to see why IPS is the tech of choice for graphics professionals.
CAUGHT IN LIMBO: VA panels would suit cult smash hits such as Limbo well
The last of our trio of panel technologies is VA or 'Vertical Alignment'. There are two types of VA panels, PVA (Patterned Vertical Alignment) and MVA (Multidomain Vertical Alignment).
PVA is more common, but both share the same basic characteristics and give similar image quality. For the most part, VA panels fall half way between TN and IPS technology. In terms of cost, colour accuracy and pixel response, VA panels split the difference.
That said, VA screens also have a number of distinct characteristics that set them apart. Most notably, the default position of the liquid crystals in a VA pixel blocks light from passing through. The upshot is that VA screens deliver the deepest, inkiest blacks of any panel type, and the best static contrast ratios.
Colour saturation is another plus point for VA screens, even if outright colour accuracy is a click or two behind the best IPS screens.
Colour gamut is another VA strong point. Like IPS technology, VA panels are typically true 8-bit per colour channel. That means colour dithering isn't necessary.
Overall, VA panels give the most vibrant, eye-catching image quality of any LCD technology. The richness and depth of a good VA monitor is spectacular. For that reason, many high-end HDTVs, including Samsung and Sony sets, use PVA LCD panels.
If VA technology does have a weakness, it's pixel response. In an attempt to reduce response times, many VA monitors use a technology known as pixel overdrive. While it can be effective for speeding up pixel response, it creates problems of its own, including input lag and inverse ghosting.
The spiel here involves altering the colour of a pixel. That requires a change in the voltage applied. The idea behind overdrive is to either increase or reduce the voltage fed to any given pixel more acutely than required for the target colour state. This accelerates the pixel towards the new colour state more rapidly. Before the pixel can overshoot the target colour, the voltage is normalised.
NEW KEN ON THE BLOCK: Badly overdriven panels can exhibit inverse ghosting, blighting your image with nasty colour trails
That's the theory, at least. Overdriven panels are definitely sharper when displaying movement, but close inspection of some overdriven monitors reveals something slightly rotten.
The first problem is usually referred to as inverse ghosting. This often manifests as a trail of shadows in the wake of a moving object, approximately in the opposite colour to that object. It's quite distinct, therefore, from the smeared trail seen on monitors with poor pixel response.
This is due to excessive overdrive leading to pixels overshooting the required colour state. Inverse ghosting can affect both TN and PVA panels with overdrive technology, but the other major problem – input lag, seems to be restricted to PVA screens.
The problem here is a measurable delay between the video signal being sent to the monitor and the screen responding with a refreshed image. Typically, this is noticed as a lag between a physical mouse input and the movement of the cursor, crosshair or application window on the screen.
Of course, the method of processing a digital signal results in at least some lag on all LCD screens compared to the instantaneous output of an analogue CRT monitor. Using a CRT monitor in cloned mode as a control device, LCD screens usually lag behind by 10 to 20 milliseconds. With some overdriven screens, this increases to 50 milliseconds or more.
The result is a sticky, disconnected feel on the desktop. That's a serious problem for gaming, and can make first-person shooters in particular almost unplayable.
That's the major panel technologies all summed up, but there are one or two universal issues to address. The first is video interfaces.
HARD TO PORT: The difference in display ports can seem confusing, but you can connect all of them up with the right cables
In theory, all the major digital interfaces are quite similar. You can't see the difference between DVI, HDMI and DisplayPort on your screen.
In practice, however, HDMI can present problems. With certain video card and driver combos, HDMI connections can throw up scanning issues that prevent the panel running pixel for pixel. In other words, you can't achieve native resolution, and that's critical for any LCD.
Admittedly, most PCs won't suffer from this problem, but when it does happen, it can be insurmountable short of buying a new video card. Our advice is not to go with any monitor that is restricted to HDMI.
Next up are the related issues of resolutions and aspect ratios. For the most part, the monitor industry has settled on full HD 1080p or 1,920 x 1,080 for the former and therefore 16:9 for the latter. The first implication of this is that it usually doesn't matter what size screen you go for, your resolution and desktop space or in-game detail will be the same.
Indeed, you could argue larger screens look worse. You just end up with bigger, jaggier looking pixels. However, if you mainly use your PC for gaming, a bigger screen gives you the option of sitting further away. Larger panels are also handy for watching TV and movies, but there are a few exceptions to this rule of ubiquitous 1080p.
A few monitors are still available in 16:10 aspect. Most common among these are 24-inch panels with 1,920 x 1,200 pixel grids. That's a useful dollop of vertical pixels. And let's be clear, vertical pixels are really useful for normal PC usage rather than watching HD movies.
STYLE ICON: Watch 3D and look like Michael Caine with Nvidia's 3D Vision specs
A few monitors are available with the slightly higher 2,048 x 1,152 resolution. The problem is, it's only a small increase over 1080p, and it's still 16:9. Finally, at the top end you have the two ultra-high resolution panels in the shape of 27-inch running 2,560 x 1,440 pixels and 30-inch 2,560 x 1,600.
We've extensive experience running both of those options and we heavily favour the latter. It's a subjective issue, but the 30-incher feels larger, more expansive and more luxurious well beyond the extra three inches and 160 vertical pixels.
Anyway, the great shame about these panels is that prices haven't really shifted since the first 30-inchers appeared five or six years ago. You're still looking at the best part of a grand for a 30-incher. The 27-inch alternative can be had from around £500, but that's an awful lot to spend on something ever so slightly suboptimal.
By far and away and without a shadow of a doubt, the best long term investment you can make for your PC is a decent screen. Repeat, LCD screen.
That's especially true at the top-end of the market, where some specs have stagnated. Back in 2006, the pinnacle of PC screendom was 30 inches and a native resolution of 2,560 x 1,600. Fast forward to the dawn of 2012 and absolutely nothing has changed. That's still as good as it gets.
In fact, if anything, prices of premium panels have hardened. Premium 24-inch monitors based on the better VA and IPS panels are quite possibly more expensive than they were five or six years ago. The problem is the market for higher-priced panels – there isn't one.
People buy almost purely on price; they just want cheap and cheerful. That said, this obsession with cheaper screens means the focus is on squeezing the most out of a sub-£300 budget.
Today, that figure doesn't just secure full HD resolutions and stretch to 27-inch and even 28-inch monitors, it also bags you a multi-function monitor packing everything from an integrated TV tuner to full stereoscopic 3D support using the technology of your choice.
Until recently, what you wouldn't get was anything other than TN technology for the panel, but there are now some exceptions. Along with some affordable VA panels, the new kid on the block is e-IPS tech, which is effectively a cheaper version of the IPS screens favoured for their colour reproduction and found in many premium devices including, yes you guessed it, Apple's iPhone and iPad gadgets.
As for the TN masses, the good news is that the technology continues to improve, closing the gap with IPS and VA. It's also worth noting that the increasingly widespread use of LED backlighting, even at the arse end of the market, has given TN a kick up the backside too.
All of which means there's serious value to be had if you know what you're buying, which is exactly where this month's LCD panelfest comes in.
Every screen purchase should start from a position of informed awareness. You need to know what you're buying and that means getting to grips with the different panel technologies. Yup, we have been here before, but given the lengths some monitor makers go to obscure and obfuscate the underlying technology, it's more critical than ever to know your TNs from your PVAs.
Twisted Nematic
I DREAM OF 3D: If slaying dragons in 3D appeals then look for a screen with 3D support
From the top, the cheapest and most commonly used panel tech is our old friend TN. Otherwise known as 'twisted nematic', in layman's terms the thing that really matters about TN technology is that the liquid crystals in each picture cell are effectively fixed at one end. When an electrical current is applied, the crystals twist rather than rotate.
This explains TN's strengths and its weaknesses. The tension involved in twisting crystals in one direction means they pop back the other way more rapidly. The result? Fast pixel response.
Of course, with one end fixed, you never get the full rotation achieved by other LCD tech, which means light isn't managed as accurately or blocked as fully. Result? Inferior colour accuracy, less expansive viewing angles and poorer contrast.
One of the specific consequences of the restricted crystal articulation is the need for dithering. TN panels can't natively display as many colours as IPS and VA screens. The solution involves forcing pixels to jump rapidly between two colour states in order to fool the human eye into observing a third, incremental colour. In theory, it should be invisible. In practice, it's sometimes possible to see the pixels fizzing away as they hop between colours.
Everything is relative though. Ongoing improvement of TN technology has given us panels superior in some regards to IPS panels of six or seven years ago.
What's more, it's not just the panel technology that has improved. The market-wide shift from CCFL backlights to LED technology has been a big help for TN screens. You get a broader spectrum of light, which helps compensate for the inherently poor colours. So, TN monitors with LED backlights are more vibrant and sock you with more saturated colours. Yay!
Despite all of this, there are limitations to TN, and they can be spotted on the spec sheets. That's true even when the monitor maker doesn't deign to mention the panel type. Unfortunately, that's pretty frequent.
Anyway, the markers you're looking for go something like this. Start with the viewing angles, the metrics manufacturers use vary, but if either figure is under 170°, you're looking at a TN. Typically a vertical angle of 160° really gives the game away.
The other major give away is contrast. The tricky thing here is that dynamic contrast – in other words, contrast achieved by modulating the backlight - is often the only figure quoted. Any figure of roughly 5,000 to one or greater will be the dynamic rating. If it's lower than that, it's likely to be contrast with a static backlight.
In-Plane Switching
THE WINKING SKEEVER: "Skyrim belongs to the Nords!"
Until recently, anything capable of 1,000 to one or more for static contrast was very likely to be VA or IPS. More recently, TN monitors capable of 1,000 to one static contrast have appeared.
At the same time, VA and IPS panels have upped their game. So any quoted figure above 1,000 to one (but below 5,000 to one) will indicate a panel other than TN.
The final give away is price, but here again, things have begun to change. Until recently, VA and IPS panels were always much more expensive. The good news is that lower cost derivatives, including e-IPS and MVA, are becoming ever more common. It's now possible, for instance, to buy a 24-inch MVA screen for under £180. If that's TN, what about the other two?
Our next candidate is 'In-Plane Switching' or IPS technology. It occupies completely the opposite end of the scale from TN for everything from price to colour accuracy.
Critically, where other panel technologies include a single controller transistor per subpixel, IPS packs a pair and offers superior crystal control and, in turn, the best colour accuracy. Of course, increase a product's complexity and you increase costs. But that's not the only downside – the extra transistors also block light. That makes IPS notably less vibrant and saturated than the best VA panels.
Another upside of IPS is extremely wide and consistent viewing angles. Unlike TN crystals with their rooted ends, the liquid crystals in an IPS panel rotate fully about their axis. That matters because it allows them to present a more consistent face to the viewer at varying angles and means a more constant quantity of light passes the red, green and blue subpixels regardless of the viewing angle. In other words, you don't get wonky colours if you sit in an off-centre position at your desk.
There is, however, a snag. That greater range of crystal articulation translates into longer response times when transitioning between extreme colours. The longer that process takes, the blurrier a panel looks when rendering moving images.
That said, just as TN technology is closing the gap for colours and contrast, IPS screens keep getting faster. Factor in the static fidelity advantages and it's easy to see why IPS is the tech of choice for graphics professionals.
Vertical Alignment
CAUGHT IN LIMBO: VA panels would suit cult smash hits such as Limbo well
The last of our trio of panel technologies is VA or 'Vertical Alignment'. There are two types of VA panels, PVA (Patterned Vertical Alignment) and MVA (Multidomain Vertical Alignment).
PVA is more common, but both share the same basic characteristics and give similar image quality. For the most part, VA panels fall half way between TN and IPS technology. In terms of cost, colour accuracy and pixel response, VA panels split the difference.
That said, VA screens also have a number of distinct characteristics that set them apart. Most notably, the default position of the liquid crystals in a VA pixel blocks light from passing through. The upshot is that VA screens deliver the deepest, inkiest blacks of any panel type, and the best static contrast ratios.
Colour saturation is another plus point for VA screens, even if outright colour accuracy is a click or two behind the best IPS screens.
Colour gamut is another VA strong point. Like IPS technology, VA panels are typically true 8-bit per colour channel. That means colour dithering isn't necessary.
Overall, VA panels give the most vibrant, eye-catching image quality of any LCD technology. The richness and depth of a good VA monitor is spectacular. For that reason, many high-end HDTVs, including Samsung and Sony sets, use PVA LCD panels.
If VA technology does have a weakness, it's pixel response. In an attempt to reduce response times, many VA monitors use a technology known as pixel overdrive. While it can be effective for speeding up pixel response, it creates problems of its own, including input lag and inverse ghosting.
The spiel here involves altering the colour of a pixel. That requires a change in the voltage applied. The idea behind overdrive is to either increase or reduce the voltage fed to any given pixel more acutely than required for the target colour state. This accelerates the pixel towards the new colour state more rapidly. Before the pixel can overshoot the target colour, the voltage is normalised.
Tricks of the trade
NEW KEN ON THE BLOCK: Badly overdriven panels can exhibit inverse ghosting, blighting your image with nasty colour trails
That's the theory, at least. Overdriven panels are definitely sharper when displaying movement, but close inspection of some overdriven monitors reveals something slightly rotten.
The first problem is usually referred to as inverse ghosting. This often manifests as a trail of shadows in the wake of a moving object, approximately in the opposite colour to that object. It's quite distinct, therefore, from the smeared trail seen on monitors with poor pixel response.
This is due to excessive overdrive leading to pixels overshooting the required colour state. Inverse ghosting can affect both TN and PVA panels with overdrive technology, but the other major problem – input lag, seems to be restricted to PVA screens.
The problem here is a measurable delay between the video signal being sent to the monitor and the screen responding with a refreshed image. Typically, this is noticed as a lag between a physical mouse input and the movement of the cursor, crosshair or application window on the screen.
Of course, the method of processing a digital signal results in at least some lag on all LCD screens compared to the instantaneous output of an analogue CRT monitor. Using a CRT monitor in cloned mode as a control device, LCD screens usually lag behind by 10 to 20 milliseconds. With some overdriven screens, this increases to 50 milliseconds or more.
The result is a sticky, disconnected feel on the desktop. That's a serious problem for gaming, and can make first-person shooters in particular almost unplayable.
That's the major panel technologies all summed up, but there are one or two universal issues to address. The first is video interfaces.
HARD TO PORT: The difference in display ports can seem confusing, but you can connect all of them up with the right cables
In theory, all the major digital interfaces are quite similar. You can't see the difference between DVI, HDMI and DisplayPort on your screen.
In practice, however, HDMI can present problems. With certain video card and driver combos, HDMI connections can throw up scanning issues that prevent the panel running pixel for pixel. In other words, you can't achieve native resolution, and that's critical for any LCD.
Admittedly, most PCs won't suffer from this problem, but when it does happen, it can be insurmountable short of buying a new video card. Our advice is not to go with any monitor that is restricted to HDMI.
Next up are the related issues of resolutions and aspect ratios. For the most part, the monitor industry has settled on full HD 1080p or 1,920 x 1,080 for the former and therefore 16:9 for the latter. The first implication of this is that it usually doesn't matter what size screen you go for, your resolution and desktop space or in-game detail will be the same.
Indeed, you could argue larger screens look worse. You just end up with bigger, jaggier looking pixels. However, if you mainly use your PC for gaming, a bigger screen gives you the option of sitting further away. Larger panels are also handy for watching TV and movies, but there are a few exceptions to this rule of ubiquitous 1080p.
A few monitors are still available in 16:10 aspect. Most common among these are 24-inch panels with 1,920 x 1,200 pixel grids. That's a useful dollop of vertical pixels. And let's be clear, vertical pixels are really useful for normal PC usage rather than watching HD movies.
The best eyeful
STYLE ICON: Watch 3D and look like Michael Caine with Nvidia's 3D Vision specs
A few monitors are available with the slightly higher 2,048 x 1,152 resolution. The problem is, it's only a small increase over 1080p, and it's still 16:9. Finally, at the top end you have the two ultra-high resolution panels in the shape of 27-inch running 2,560 x 1,440 pixels and 30-inch 2,560 x 1,600.
We've extensive experience running both of those options and we heavily favour the latter. It's a subjective issue, but the 30-incher feels larger, more expansive and more luxurious well beyond the extra three inches and 160 vertical pixels.
Anyway, the great shame about these panels is that prices haven't really shifted since the first 30-inchers appeared five or six years ago. You're still looking at the best part of a grand for a 30-incher. The 27-inch alternative can be had from around £500, but that's an awful lot to spend on something ever so slightly suboptimal.