My subjective impressions
Now you've seen the nerdy empirical measurements of the PB287Q versus its 27" IPS sibling. One could cynically page through the results and conclude that the traditional TN panel weaknesses remain: lower contrast ratios, a narrower color gamut, and color shift at less-than-optimal viewing angles.
That's not the whole story, though. I spent many hours peering at the PB287Q and the IPS-based PB278 during this review process. My basic impression is that, on a whole host of fronts, the contest between the two is incredibly close.
The traditional TN weaknesses are substantially muted in the PB287Q. This thing really is nothing like one of those terrible, cheap laptop displays. Most folks simply won't notice any issues with contrast and viewing angles during seated desktop use.
My son and I cycled through a series of landscape pictures from InterfaceLift on the PB287Q and the PB278, side by side, trying to discern the differences between the two. They were really hard to pick out. With most images, the color reproduction was essentially equivalent. Having seen our color gamut readings, I was able to select an image with lots of deep reds and blue-violet tones that stressed the PB287Q's weak points. Then we could detect some differences, but that was kind of cheating.
The flip side of that coin is that the PB287Q's higher pixel density can be hard to discern when you're sitting ~24" from the screen. One reason: even though lots of cameras can outstrip this monitor's eight-megapixel resolution, not all of the images they capture are sharp enough to take full advantage of the extra resolution. You'll notice the increased pixel density in some photographs by concentrating on sharp, high-contrast edges, where individual pixels are easier to see at conventional PPIs. In rare cases, with the right source image, the difference between the two monitors can be striking.
Gaming is another story. Taking advantage of 4K requires the right game, with the right assets. With older or lower-fidelity games, what you may notice most often is sharper edges and more easily discernible polygon intersections in lower-poly models. You'll see that your sniper scope is octagonal rather than round, which is a little disappointing. Games that have higher-poly models are more visually rewarding.
The added sharpness possible in textures and shaders is the candy, the really sweet thing about 4K. Some titles have it. For instance, the PB287Q's single-tile goodness banished the screen-centering problems I saw in Tomb Raider on a dual-tile setup with the Radeon R9 295 X2, and the Radeon responded by pumping out some of the most gorgeous visuals you'll see anywhere in real-time graphics. I've attached a couple of screenshots in the image gallery below from Call of Duty: Ghosts that demonstrate its every-pixel detail, too.
Seriously, though, even in the best games, you'll have to stop and peer into the screen in order to take in the difference between 4K and 2560x1440. During fast action, it's almost impossible to perceive. What you will notice, even on some of the fastest GPU hardware like the GeForce GTX 780 Ti SLI and Radeon R9 295 X2 configs I used for testing, is the performance hit when going to 4K.
Not that there's a real problem here. In some cases, like Tomb Raider, one or two of today's best GPUs will be fast enough that the 4K performance hit simply doesn't matter. The game will still run fluidly. In others, well, the PB287Q looks awfully nice when scaling games up from 2560x1440. You're free to enjoy the high-PPI goodness in desktop applications, where the benefits are clear, and switch into a lower-PPI mode for gaming—as long as, you know, Asus updates the firmware to expose the correct video modes.
You've gathered by now that the PB287Q and monitors like it represent a new class of desktop display. If you're looking to upgrade or to build an all-new system, this monitor should definitely be on your radar. The core display technology, as we've seen, is surprisingly good for a TN panel, and Asus has wrapped a nice set of externals and extras around it. A year ago, I would have recommended a 27" IPS panel for a PC enthusiast considering this class of desktop monitor. Now, I'd recommend the PB287Q for most folks, instead. The added resolution and slightly larger screen are obvious and worthwhile upgrades.
The one thing that may freeze you from pulling the trigger right now on the PB287Q is, oddly enough for the monitor market, the promise of better things coming soon. Acer has already announced a 4K monitor with G-Sync that may be based on this very same panel. It's supposed to ship this quarter, and we wouldn't be shocked to see others following suit eventually. There's also the prospect of cheaper 4K monitors based on IPS and other display technologies, and eventually we should see monitors that implement the new VESA Adaptive-Sync spec, as well. Any such products are likely to cost more than the PB287Q, though, and none of them are available today.
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