Welcome, everybody, to the first in an impossibly exciting new series of posts in which I tell you why you need to buy stuff. Or maybe why you don’t. If that sounds a lot like what I’ve already been doing with Week In Tech, there’s a twist.
The point is that a lot of jargon gets thrown around when it comes to PC hardware. Too often assumptions are made. Assumptions about what is good and bad. Assumptions about what everybody understands or cares about. With all that in mind, we thought it would be good to go back to basics with stuff that sometimes seems obvious but actually isn’t. We’ll start with IPS panel technology in PC monitors. If you’re thinking about buying a new screen, you need to know about this.
Over the last year or two, the usual refrain greeting a new PC monitor has been either, ‘spec looks good, pity it’s not IPS’ or, ‘at last, it’s a something-or-other monitor with an IPS panel’. Either way, IPS is the reference point by which all PC monitors seem to be judged, the assumed preference among all mankind. Why is that, how does IPS work, is it all it’s cracked up to be? Let’s find out.
What IPS is
IPS, then, stands for in-plane switching, the implications of which we’ll come to in a moment. It’s a type of thin-film transistor LCD panel. LCDs of various kinds have dominated the display market for years, of course.
I reckon we’ve Apple to thank for both increasing awareness of IPS technology and wider use of it in devices and monitors. It wasn’t until Apple began to proselytise on all things IPS with the introduction of the iPhone 4 that the concept really entered the wider public’s imagination. Suddenly, IPS was a ‘thing’.
That matters because IPS is more expensive than some alternative LCD technologies. So device and monitor manufacturers are not going to use it unless they’re convinced punters are willing to pay extra for it. And that’s what Apple did for the world. It put punters in the frame of mind to pay a premium for IPS rather than simply opt for the cheapest display going.
Anyway, IPS is not fundamentally different to other liquid crystal display technologies. The same basic principles apply. A grid of liquid crystal pixels sit in front of a backlight and act as shutters, either allowing light to pass through or blocking it out.
4K ubertrons grab the headlines, but IPS vs TN is the critical comparison
It’s how well IPS does this job of blocking light or allowing it to pass through that distinguishes in-plane switching LCD panels from other technologies. That means, firstly, that whatever anybody says, the best of IPS is not life-alteringly different or superior to the best of other LCD technologies. IPS is not like OLED technology which works on entirely different principles and can achieve things LCD cannot, like effectively infinite contrast.
It means the inherent pros and cons of any LCD panel are present in an IPS panel. And it means that, in theory, IPS can be had with the very same accompanying technologies as any other LCD panel, be that an LED backlight or frame-syncing technology.
However, there are a couple of things that IPS does better than any other currently available LCD panel tech and which explain its hallowed status among the LCD-screen cognoscenti. The most obvious and important are viewing angles and colour accuracy – two metrics that are actually closed linked to one another.
The reasons why are a bit technical. But the basics go something like this. In a IPS LCD cell, the liquid crystals can freely rotate. This is good because it makes for fine control over a broad range of light transmission. And it’s managing light transmission that determines both the range of colours a panel can display and the scope of its viewing angles.
The rival screen types
By contrast, in a TN panel, which is an alternative and cheaper panel tech, the movement of the crystals is restricted. Think of TN as having crystals fixed at one end and then bent or twisted rather than rotated. Hence the TN terminology, which stands for twisted nematic.
Anyway, the point is that there’s less range of articulation and thus more limited control over light transmission. On the other hand, the more limited range of TN technology makes for quicker reponses and faster-switching pixels and vice versa for IPS.
Where things get a little more complicated is when you introduce the third major panel technology, known as VA or vertical alignment, which also has superior liquid crystal articulation compared to TN. It offers some of the advantages of IPS technology but combines them with better contrast and yet worse viewing angles and response.
For the record, it’s also worth noting that there are a number of IPS-alike LCD technologies that go by another name. Samsung, for instance, has its own PLS panel technology. AU Optronics offers AHVA. And several monitor makers attach prefixes to IPS panels to distinguish various generations and quality levels, such as S-IPS, H-IPS and AH-IPS panel upgrades and low-cost e-IPS alternatives.
What’s more, the latter are often hobbled when it comes to colour fidelity, dropping down to 6-bits per colour channel compared to the 8-bit and 10-bit capabilities of more expensive IPS screens. Fundamentally, however, the mechanics and characteristics of each compared to other non-IPS panel techs are broadly the same. More accurate colours. Better viewing angles. Yada yada.
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With the theory in the bag, the question is whether IPS is truly worth the price premium, especially in the context of PC gaming where pixel response is arguably as important as things like colours, contrast and viewing angles. To that question, the simple answer is yes. But it does require qualification.
Part of the problem is the relatively wide variation within a given panel type. Not all IPS panels are equal. Some older IPS panels can suffer from a distracting white glow that shifts across the screen as you move your head, for instance. Ditto TN – there’s a whole spectrum of TN panels out there.
But some generalisations can be made. IPS definitely does look better. Exactly how much better will depend on the screen in question and you particular sensibilities.
Why IPS is best
Again, it’s colours and viewing angles that most stand out. All but the most recent TN panels, for instance, have an ever so slightly washed out appearance. The colours look a little off, a but dull. Depending on what’s being displayed, you can often see a clear shift in colours from top to bottom of the panel, too. That’s the poor viewing angles. Black tones can have a slightly purply-blue tinge, to boot.
By comparison, a decent IPS panel just looks right. It’s vibrant without being OTT. Viewing angles are effectively a non issue. And black tones don’t suffer any colour corruption even if fully black pixels aren’t actually possible. A little light always leaks through with any LCD. You also get perfectly smooth colour gradients with a good IPS panel. TN screens almost always have visible banding. They simply can’t render enough colours for completely smooth transitions.
As for pixel response, opinions vary. I personally think IPS panels are quick enough for almost all gaming. If your gaming life is absolutely and exclusively about hair-trigger shooters, OK, you’ll want the fastest response, lowest latency LCD monitor. And that means TN. For the rest of us, and certainly for those who place even a modicum of importance on the visual spectacle of games, I reckon IPS is clearly the best panel technology.
I’m also recommending that most of you steer clear of VA panels. Some can suffer from wonky colours and none of them have great pixel response. Input lag is a common issue with VA, too, probably because panel makers overdrive the snot out of them to get the pixels moving a bit. For the same reason, inverse ghosting is a common problem with VA, too. It’s not to say that they’re all bad. But unless you know exactly what you are doing and precisely what you are buying, I think the risk is too high.
Acer’s 27-inch, 1440p, 144Hz, IPS effort does G-Sync and seems to offer (almost) everything in one monitor…
As for TN, complicating the issue of late are the very latest panels in cheap 4K monitors. They offer by far the best viewing angles and colours I’ve ever seen from a TN panel. The gap to IPS hasn’t quite been closed, but these are very nice screens indeed. However, that quality of TN is currently limited to those 28-inch 4K models. And 4K just isn’t a practical screen res for most of us given the load it puts on graphics cards.
Notably, the latest 27-inch 2,560 by 1,440 pixel TN panels aren’t nearly as good. In fact, I’ve found them a real disappointment for basic panel quality. That’s something 120Hz refresh rates and frame-syncing snazziness like Nvidia’s G-Sync technology does nothing fix.
Of course, 120Hz and frame-syncing is certainly sexy stuff. But that’s another story for another day. In the meantime, know this: An IPS monitor can be had for as little as £130 / $150, maybe a bit less if you shop around. So IPS is now genuinely affordable. Also, shout out below with your views and experiences on IPS and TN tech and let me know if what other core PC gaming technologies you’d like to see taken back to basics.