The majority of monitors, especially newer models, display excellent grayscale tracking (even at stock settings). It’s important that the color of white be consistently neutral at all light levels from darkest to brightest. Grayscale performance impacts color accuracy with regard to the secondary colors: cyan, magenta, and yellow. Since computer monitors typically have no color or tint adjustment, accurate grayscale is key.
We approached the PA279Q a little differently than other screens we’ve reviewed due to its greater number of calibration options. Here is our baseline measurement of the Standard mode at default settings.

In Standard mode, you can adjust the color temperature preset, but not the RGB sliders. The default option is 6500 K. But as you can see, it runs a little too red. The error becomes visible at 40 percent brightness and above. Setting the PA279Q to the 9300 K option causes a slight blue tint to the white parts of the image.
There are two ways to improve the grayscale. One is to configure the User modes, which allow custom tailoring of both grayscale and color (though not without penalties, as you’ll see in the color section of the review). If you do that, you’ll be rewarded with excellent results.

It doesn’t really get better than this. Check out the 60-percent brightness level, which has a Delta E error of only .14! If you choose to use the like that, be sure to check out our color results on page seven first.
The compromise is to be found in the sRGB and Adobe RGB modes.

This is a pretty good chart, calibrated or not. Asus advertises a high degree of accuracy for the PA279Q and it certainly delivers on that promise. Visible errors don’t occur until 90 percent brightness, and then only barely. You get the exact same results in the Adobe RGB mode.
Let’s bring our comparison group back into the mix. Since we chose sRGB as the best all-around picture mode, the numbers below represent that mode.

The stock number is quite good, bested only by HP's E271i. Even the factory-calibrated Samsung S27B970D isn’t quite as good, yielding a stock error of 2.56 Delta E. We’re picking nits, but the PA279Q does undercut that screen’s price by almost $300.
Since we couldn’t adjust grayscale in sRGB mode, the final number doesn’t change much.

The other displays rank higher by virtue of their available RGB adjustments. But the PA279Q still comes in well under the visible error level of three. If you employ User mode, you can get the average Delta E down to .71 which ties the Samsung for lowest grayscale error we’ve measured. It’s unfortunate that the color gamut is not as accurate in the User modes.
Gamma Response
Gamma is the measurement of luminance levels at every step in the brightness range from 0 to 100 percent. This is important because poor gamma can either crush detail at various points or wash it out, making the entire picture appear flat and dull. Correct gamma produces a more three-dimensional image, with a greater sense of depth and realism. Meanwhile, incorrect gamma can negatively affect image quality, even in monitors with high contrast ratios.
In the gamma charts below, the yellow line represents 2.2, which is the most widely accepted standard for television, film, and computer graphics production. The closer the white measurement trace comes to 2.2, the better.

Again, this is the sRGB mode. However, this gamma result is nearly identical to the Standard, User, and Adobe RGB modes. The tracking is fairly flat and rides just below 2.2. The maximum error here is less than 4 cd/m2.
Here’s our test group again for the gamma comparisons.

Asus' PA279Q is among the very best for gamma tracking. This level of consistency is only present in three other monitors we’ve tested this year. The S27B970D is exceptional, and Asus trails it by only a tiny bit.
We calculate gamma deviation by simply expressing the difference from 2.2 as a percentage.

The five-percent deviation from 2.2 is fairly small, representing no more than 4 cd/m2. Again, the PA279Q is among the best screens we’ve measured for gamma performance.
- Asus PA279Q, The Cadillac Of Monitors?
- Packaging, Physical Layout, And Accessories
- OSD Setup And Calibration Of The PA279Q
- Measurement And Calibration Methodology: How We Test
- Results: Brightness And Contrast
- Results: Grayscale Tracking And Gamma Response
- Results: Color Gamut And Performance
- Results: Viewing Angle And Uniformity
- Results: Pixel Response And Input Lag
- Asus' PA279Q May Very Well Have It All
And are not happy with Dell and HP...
You should be smiling now!
Also at some places you can even get this around $800..
Liking the new Eizo model w/ 240 Hz mode too.
Not this year but sometime next year I'd love to upgrade my system. I built my current workstation when the phenom 1 chip came out and other than a CPU upgrade after the phenom 2 came out and graphics card revision (old one died) I've not needed to do anything else to it. Starting to get a bit long in the tooth though.
120 cd/m2 would be ideal for a darkened room but we calibrate to 200 to better replicate an average viewing environment. Most graphics pros would opt for a darker space but the average user will have more ambient light to compete with. Since we're reviewing all types of displays, we need to place them on equal footing.
-Christian-
If you want "pixel perfect" from Achieva, it'll cost you the same. Quite a gamble, big savings vs. a few dead pixels.
It's technically the same panel, but it's a rejected panel by Apple and sold to 3rd parties like Achieva. That means dead pixels and irregular lighting and color are normal. That also means fewer input options (to save money), hardly any screen controls and settings (to save money), no height or tilt adjustment (to save money), cheaper components internally (to save money), and of course, a very weak warranty.
Tie all this in with poor build quality (some of those displays have been reported as having dirt behind the panel!), and IMO it's just not worth the savings/risk. And considering manufacturers of these "affordable" QHD monitors use cheaper internal components, I'd be most concerned about how long the thing will last even if I got a perfect panel. That would always be in the back of my mind every time I touched the power button.
So while you may be saving 50%, you are paying elsewhere by short changing yourself. I know what 5 dead pixels are like on a QHD monitor, because I had them on my ASUS PB278Q 27". They were concentrated within a 4-inch square in the middle of the screen and impossible to not notice. That monitor is known to have a pretty high dead pixel rate. I promptly returned it to Fry's and stepped up to the more professional factory Adobe RGB calibrated LG 27EA83.
In addition to 10tacle's reason, you also lose the USB ports on that model.
Guess that kinda depends. I don't know why many people would spend $800+ on a 27" display only to hook it up to a cable box or PS3. That much money will get you a very nice, rather large, TV.
As do I. Sadly, the price premium for 16:10 over 16:9 is pretty ridiculous. A quick search on Newegg shows the only 2560x1600 monitor with USB 3.0 is a $1500 30" Lenovo.
I only wish this thing was 120Hz
Liking the new Eizo model w/ 240 Hz mode too.
60 Hz is really about all that's needed to fool the human eye.
TVs went to 120 Hz because of a problem peculiar to displaying movies. Most movies were shot at 24 fps. 60/24 = 2.5 which isn't an even integer. If you try to display them on a 60 Hz screen, you end up having to show one movie frame for 2/60 sec, the next frame for 3/60 sec, then repeat. The result of this uneven timing is something called judder, where smooth motion (especially panning shots) appear to stutter.
With a 120 Hz refresh, you can show each movie frame for 5/120 sec, and a smooth panning shots remain smooth. 240 Hz is just the same thing except for 3D video - 120 Hz for the left eye, 120 Hz for the right eye.
So unless you're planning to watch a lot of 24 fps movies, 60 Hz is just fine. And unless you're planning to watch 3D movies shot at 24 fps, 240 Hz is overkill. If you're watching video shot at 30 or 60 fps, it'll look the same at 60 Hz, 120 Hz, or 240 Hz.