Monoprice Zero-G 42891 QHD 165 Hz Gaming Monitor Review: And Prices Continue to Fall

The Monoprice Zero-G 42891 is a 32-inch QHD/VA curved gaming monitor with 165 Hz, Adaptive-Sync, HDR and extended color.

Monoprice Zero-G 42891
(Image: © Monoprice)

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The Zero-G 42891 includes six picture modes. Standard is the default and best option with calibration controls available. While adjustment is not strictly necessary, there are visible gains to be had.

Grayscale and Gamma Tracking

Our grayscale and gamma tests use Calman calibration software from Portrait Displays. We describe our grayscale and gamma tests in detail here.

Though the average error isn’t too high, there is a visible blue tint in the brighter parts of the image. It’s more obvious in neutral gray and white tones; primary colors aren’t affected. Calibration isn’t strictly necessary, but I recommend trying the settings from page one. Gamma tracks well until the 60% step where it goes a bit light. However, this is a minor error.

The RGB sliders have low resolution, which means each click results in a big change. That makes a precise calibration difficult, but I got all the DeltaE numbers under three after a little trial and error. Gamma is a little lighter at 80 and 90 percent, but this is an acceptable compromise. The picture is visibly improved.


The Zero-G 42891’s 3.76dE grayscale error is average among low-priced gaming monitors. You can enjoy it without calibration, but improvements are possible. I couldn’t get the end result under 1dE like the others but at 1.57dE, there are no visible problems.

Gamma tracking is good in the lower two-thirds of the brightness scale but at 80% brightness, the values are a tad too bright. In practice, this reduces highlight detail just a little. I’m picking nits for sure. A value range of 0.24 and a 3.64% deviation is still in the very good category.

Color Gamut Accuracy

Our color gamut and volume testing use Portrait Displays’ Calman software. For details on our color gamut testing and volume calculations, click here.

You can see the Zero-G 42891’s wide color gamut clearly represented in the charts. Only green is a little under-saturated, like nearly all extended color monitors. The only issues with the default chart are hue errors in cyan and magenta. Saturation targets are very close to correct.

Calibration fixes the hue errors and brings the saturation values even closer to perfect. This is excellent performance in the DCI-P3 realm. My only complaint is there’s no sRGB mode. While few users will care about this, the choice to use the correct gamut with SDR content should be there.


With a calibrated gamut error of just 1.62dE, the Zero-G 42891 takes the color gamut accuracy crown in this competitive field. It impressively pips the Corsair, which costs more than double the price. This accuracy is great to see from any monitor and even better from a budget screen.

The Zero-G 42891 has a tick more color volume than most wide gamut monitors I’ve tested. It has just a little more green, which balances well with the spot-on red and blue primaries. Obviously, sRGB volume is very high because there’s only one gamut available. If you want to use the Zero-G 42891 in a color-critical application, you’ll need a compensation profile in place.

Christian Eberle
Contributing Editor

Christian Eberle is a Contributing Editor for Tom's Hardware US. He's a veteran reviewer of A/V equipment, specializing in monitors. Christian began his obsession with tech when he built his first PC in 1991, a 286 running DOS 3.0 at a blazing 12MHz. In 2006, he undertook training from the Imaging Science Foundation in video calibration and testing and thus started a passion for precise imaging that persists to this day. He is also a professional musician with a degree from the New England Conservatory as a classical bassoonist which he used to good effect as a performer with the West Point Army Band from 1987 to 2013. He enjoys watching movies and listening to high-end audio in his custom-built home theater and can be seen riding trails near his home on a race-ready ICE VTX recumbent trike. Christian enjoys the endless summer in Florida where he lives with his wife and Chihuahua and plays with orchestras around the state.

  • Gorlash
    This is very frustrating... I have a 30" 2560x1600 monitor (HP ZR30w), which I really love... it has been my treasured gaming machine for over a decade now... the only drawback, is that it doesn't have any of the modern bling - >60hz, adaptive sync, other fancy stuff...

    I would love to look at a new monitor with newer tech... but I'm still holding out for 16:10 aspect ratio... maybe I will just die here with the other old farts...