From a picture quality standpoint, this is one of the better monitors I've ever tested. The new panel technology really shines here, enabling solid color fidelity, rich black levels, and good viewing angles. Unfortunately, it's also naturally limited in scope: The price of entry is a video card capable of outputting at 4K—and $3,000.
It really comes down to how soon you need a 4K-capable display like this, as 2014 will likely see plenty of more affordable options. If time is of the essence, if you can pass the spec check, and if you can pony up the dough, we highly recommend the PQ321Q. Print designers be warned, however: the PQ321Q does not support the Adobe RGB gamut, it lives strictly within the realm of digital color.
The first thing you'll probably notice about the PQ321Q is its port selection. Older VGA inputs (the blue ones) have been slowly disappearing from monitors for a while now, but this Asus is the first I've ever reviewed that also excludes a DVI-D input (the white one). Oh, it's also huge.
Looking to the future, Asus instead includes two HDMI inputs and a DisplayPort input—both formats that can carry a 4K signal. Users will also find an RS-232C control port and audio in/out for a PC source. All of the PQ321Q's ports are located in a small cutout on the monitor's left side, while on-set controls mirror them on the right.
A strip of metallic backing along the neck is the most eye-catching design choice. Once the stand is assembled, the PQ321Q's panel can move up/down in height by almost six inches, swivel 45° to either side, and tilt forward/backward by about 25°. Oddly enough, it doesn't rotate to portrait orientation—a common feature of professional monitors. You have to install it that way, screws and all.
For all that, the PQ321Q isn't much to look at. It isn't ugly by any means, but one person's professional is another person's boring. While an angular black design looks good on almost any desktop, the Asus PQ321Q probably won't catch any admiring stares unless it's displaying a beautiful 4K image. Alongside the monitor itself, Asus throws in a DisplayPort cable, quick start guide, RS232 cable, and an optional sticker for labeling the controls on the front of the monitor.
Indium, gallium, and zinc, oh my!
IGZO stands for "indium gallium zinc oxide," and it's a fairly new semiconductor that allows both TV and monitor LCD panels to be built at higher resolutions.
What differentiates IGZO from older semiconductor types is that it uses smaller transistors—electrical pass-throughs along the conducting material. The actual transistors are smaller than in years past, which allows for more of them. The more transistors there are per inch, the more pixels, and the higher the resolution.
If you'd like more information on the use of IGZO semiconductors in display tech, check out this hands-on article over at PCWorld.
Go, Go, IGZO!
The Asus PQ321Q may not have a fancy design or any USB ports, but it's got the goods that count. The IGZO panel isn't just a fancy name or a gimmick: All 8 million pixels look great, right out of the box.
Web designers and architects may want to keep the PQ321Q on their radar as a potential investment. This Asus can output 10-bit color, and it covers the sRGB digital color space, too. Picture modes, including Standard and Vivid, can be swapped with various Gamma settings to get either an exciting, flashy look or something more professional.
I feel I should note again that this display is not capable of the Adobe RGB color standard, something which could be an instant deal breaker for print designers.
I measured very solid black levels and a respectable peak brightness, as well. Sound backlight uniformity means a very even picture, and the IGZO panel maintains good picture quality at off-angles.
One place where the PQ321Q won't be welcome is at serious gaming competitions. I ran Skyrim on Ultra settings with the resolution cranked up to 4K, and it looked beautiful.
Unfortunately, the PQ321Q's 8ms response time is a teensy bit too slow for completely lag-free gaming, and experienced gamers will notice it in more intensive titles like Starcraft or Counter-Strike. There are better choices if hardcore gaming is your bag, anyway.
Worried you won't be able to take advantage of the 4K resolution just yet? Asus has you (mostly) covered, with a side-by-side (picture-by-picture) setting that can display two 1080p images simultaneously. The integrity of the picture quality during this function is obviously lessened, but the ability to run your PS3 side-by-side with your MacBook Air could be worth it, depending on the individual.
One of the best of its kind... for now
The Asus PQ321Q is the first 4K monitor I've had the pleasure of testing, and it's a very impressive specimen. The $3,000 MSRP is hard cheese to swallow—on the other hand, you aren't buying anything less than what's advertised.
The PQ321Q's only real issue is one measured in millimeters: How soon do you need a 4K monitor? There were many more affordable 4K monitors announced at CES 2014, some even wielding an on-board Android OS. Most of the cows have yet to come to pasture, though, and the PQ321Q is here now.
If you're not interested in showy features, or if you've just got plenty of money to spare, feel free to spring for this monitor. But if you're weighing your money carefully, you may want to wait—we'll be sure to review all the new 4K displays as they become available, and it's always wise to peek at competition before you spend.
The Asus PQ321Q is an odd bird, even for a 4K panel. Instead of a single, 32-inch 3,840 x 2,160 panel, this monitor is actually two 1,920 x 1,080 panels, side-by-side—it only looks like one panel.
The panels obviously do everything in tandem, but can also be split to display two 16-inch 1080p images. What's even more impressive is how high-quality this Asus looks, right out of the box. Whether it's handling two 1080p images or a single 4K image, it's right on target.
The PQ321Q flaunts a color depth of 10 bits, which means it's capable of more color saturation than many other computer monitors, most of which utilize 8-bit color. Thus, this Asus covers a little more than the sRGB color gamut, the current digital color standard.
The Asus PQ321Q's red, blue, and green primaries weren't completely flawless, but they were well within acceptable error margins for digital color production—likewise with the cyan, magenta, and yellow secondaries. I was also very impressed with the PQ321Q's white/gray points, which were almost perfect.
When dealing with display devices, the grayscale refers to the spectrum of black/gray/white along video intensity inputs. Computer monitors create gray and white by combining red, green, and blue sub-pixels—this is called "additive color." Ideally, each point along the grayscale should correspond to the same x- and y- coordinates in the color space, to ensure that the color temperature of the grays and whites is the same. When the color temperature sways from the D65 ideal, a sum of error is recorded in DeltaE.
After a short warm-up period, the PQ321Q tested with a grayscale DeltaE of 2.27, which is quite low. Grayscales with a DeltaE of 3 or below are generally considered acceptable by modern display standards, so this is a good result.
RGB balance refers to the input level of a display's red, green, and blue sub-pixels relative to one another. Ideally, the monitor will neither over-emphasize nor under-emphasize any one sub-pixel across the grayscale intensity range, which is what helps to maintain an even correlated color temperature or white point.
I measured a very well-maintained RGB balance while testing the PQ321Q—the blue sub-pixel is favored slightly, but not overmuch, and never to the point of visibility. This isn't a perfect result, but it is very good nonetheless.
Gamma refers to the light intensity allocation to each step along the grayscale. A higher number, such as 2.6, refers to a gamma curve that very gradually leaves black and enters middle-gray and white. A lower number, such as 1.8, refers to a much faster gamma curve, one that exits black almost immediately.
We measured an almost perfect 2.4 gamma, the ideal slope for a dark or black room—which is exactly where the PQ321Q was tested. This was the pre-set in sRGB mode, so users looking for a brighter gamma (such as 2.2 or 2.0) may want to set the monitor up in Standard mode so that gamma can be tweaked more easily.
Meet the tester
Lee has been Reviewed's point person for most television and home theater products since 2012. Lee received Level II certification in TV calibration from the Imaging Science Foundation in 2013. As Editor of the Home Theater vertical, Lee oversees reviews of TVs, monitors, soundbars, and Bluetooth speakers. He also reviews headphones, and has a background in music performance.
Checking our work.
We use standardized and scientific testing methods to scrutinize every product and provide you with objectively accurate results. If you’ve found different results in your own research, email us and we’ll compare notes. If it looks substantial, we’ll gladly re-test a product to try and reproduce these results. After all, peer reviews are a critical part of any scientific process.Shoot us an email