BenQ MOBIUZ EX321UX  Monitor Review

The BenQ EX321UX has an understated appearance that works well in both an office and a gaming environment. However, the tripod legs supporting the monitor stick out considerably in front of it and take up a lot of desk space.

The build quality is great. The plastics have a nice finish, and there's no creaking in the plastic housing, though the back of the monitor does flex a bit. There are no defects in the bezels.

There are vents all around the top and bottom of the monitor to help it cool, and there seems to be a lot of empty space inside the monitor's housing for cooling. Additionally, while the remote is lightweight, it feels solid.

The ergonomics are mediocre. While it has good height adjustment and a mediocre tilt range, it doesn't swivel very much, so it's not ideal if you want to share your screen with others. Additionally, while it rotates three degrees in either direction for leveling, it doesn't rotate into portrait.

The stand is very large and takes up a lot of room in front of the monitor. However, it holds the monitor well, as it has very little wobble when bumped and recovers quickly afterward. The monitor feet aren't height-adjustable.

The thickness measurement is from the back of the monitor's support foot.

This BenQ MOBIUZ EX321UX has a remote you can use to adjust the on-screen settings. If you prefer to adjust the monitor's settings without the remote, you can also use the monitor's integrated buttons, which include an input selector key, a joystick to control the on-screen display, and a power button.

• HDMI cable
• USB-C to USB-A cable
• USB-C to USB-C cable
• Remote
• Power cable and supply
• Documentation and calibration report

The contrast is decent. When local dimming is off, deep blacks appear gray, but when local dimming is on, the contrast is excellent, and you can see fairly deep blacks next to bright highlights.

The local dimming is alright. It uses Mini LED backlighting with 1,152 dimming zones, and there's a Local Dimming setting to turn it on and off. It really improves the black levels and contrast for an impactful HDR experience, but there are some issues. There's some blooming around bright objects, like subtitles, but it's not overly distracting with most content. That said, it's more noticeable when browsing the web, so you may prefer disabling local dimming when you aren't gaming or watching content.

Using local dimming doesn't make small highlights against dark backgrounds pop more compared to not using the feature, like in a scene with a starfield. Some details are also lost in very dark scenes. However, it still improves the picture quality compared to SDR, so it's worth using local dimming in HDR.

Unfortunately, the algorithm doesn't keep up well when fast-moving objects move between the dimming zones. Transitions are choppy, and there's pulsing/flicker with small and medium-sized objects. This is distracting with fast-moving content.

Another downside is that using the OSD with local dimming enabled doesn't trigger any of the zones, so the menu is hard to see if there's a dark background on-screen.

Settings

• Color Mode: Custom (after calibration)
• Brightness: Max
• Local Dimming: On

The SDR brightness is outstanding. It easily overcomes extremely bright glare, and the brightness level remains fairly consistent with all but the smallest window sizes. The minimum brightness measurement is with Local Dimming 'Off'. If you turn it 'On', the minimum brightness is 50 cd/m².

If you turn Local Dimming 'Off', brightness decreases, as you can see below:

Settings

• Color Mode: Display HDR
• Brightness: Max
• Local Dimming: On

The HDR brightness is outstanding, and all highlights really pop. However, it doesn't follow the PQ EOTF very well, as most parts of scenes are too dark, and it has a slow roll-off near peak brightness. This prevents highlights from getting as bright as possible, but helps preserve bright details.

The 'Sci-Fi', 'Realistic', 'Fantasy', and 'Cinema' Color Mode settings don't lock out any picture settings and allow a lot of customization. However, their EOTF tracking and color accuracy were worse than 'DisplayHDR', which locks out the following settings:

• Light Tuner
• Color Vibrance
• Shadow Phage
• B.I.+
• Gamma
• Contrast
• Color Temperature

The gray uniformity is great. Though the edges of the monitor are a bit darker, it's quite uniform in the middle. You can also see the monitor's 5% gray uniformity.

The black uniformity is good. While there's a fair amount of cloudiness with Local Dimming 'Off', the black uniformity is fantastic with it 'On'.

The accuracy before calibration in the 'sRGB' Color Mode is amazing. It locks colors extremely well to the sRGB color space, and has great color accuracy. Gamma also follows the sRGB curve very closely. However, despite having good white balance, brighter colors are too warm.

Using the sRGB mode locks the following settings.

• Color Mode
  • Light Tuner
  • Color Vibrance
  • Shadow Phage
  • B.I +
  • Gamma
  • Color Temperature
  • Local Dimming
• Eye Care
  • Low Blue Light
  • Color Weakness

You have to use a less accurate mode to get access to these settings.

The accuracy after calibration is fantastic. However, some colors, such as orange, are less accurate than before calibration. The monitor only lets you improve the picture by adjusting Color Temperature and Color Vibrance, and there are no more detailed adjustments available on the monitor.

The SDR color gamut is superb. It displays most colors in sRGB and nearly all colors in Adobe RGB. Although some colors, such as red, blue, and magenta, are inaccurate in Adobe RGB, you may be able to avoid this issue with a color-managed app.

The HDR color gamut is outstanding. It displays nearly all colors in the commonly used DCI-P3 color space and a wide range of colors in Rec. 2020, and it does so quite accurately.

The HDR color volume is fantastic. It displays bright colors extremely well, though darker colors look more muted.

The horizontal viewing angle is decent. It works well if you're sharing your screen with someone who's just off-center next to you, but it washes out at wider angles.

The text clarity is superb. Enabling Windows ClearType (top photo) improves the boldness of letters. These photos are in Windows 10, and you can also see them in Windows 11 with ClearType on or off.

The direct reflection handling is okay. Bright objects don't look very distinct, as the matte screen spreads light out.

The black levels remain superbly low in bright environments.

The monitor is mediocre at absorbing light. Because light spreads across the screen, glare can still be an issue in brighter rooms.

The gradient handling is remarkable. There's minimal banding between shades of similar colors.

You don't need to use DSC to reach the monitor's max refresh rate of 144Hz over DisplayPort if your graphics card supports DisplayPort 2.1 (40Gbps or higher). Additionally, you don't need to use DSC with HDMI to reach the max refresh rate, provided your graphics card supports HDMI 2.1 (40Gbps or higher).

If your graphics card only supports DisplayPort 1.4 bandwidth (HBR3), then you need to use DSC to reach the max refresh rate.

In addition to FreeSync and G-SYNC compatibility, this monitor also supports HDMI Forum VRR.

The BenQ EX321UX has great motion handling across its VRR range. The 'OD 1' AMA has minimal blur and is fairly consistent at different refresh rates. The 'OD 3' setting has such a high CAD that it passes the limits of the chart, though you can see an alternate chart with a larger scale.

The refresh rate compliance is great. However, it's not fast enough to make full color transitions between some frames.

The CAD at the max refresh rate is impressive, and fast-moving objects look quite crisp. The '1' AMA setting has the lowest total response time and only a bit more inverse ghosting than '0'.

The CAD at 120Hz is impressive, and fast-moving objects look quite crisp. The '1' AMA setting has a lower first response time than '0' and less inverse ghosting than '2' or '3'.

The CAD at 60Hz is great, and fast-moving objects look fairly crisp. The '0' AMA setting has a lower total response time and less inverse ghosting than '1', '2', or '3'.

This BenQ MOBIUZ EX321UX doesn't have a backlight strobing feature to reduce persistence blur.

The monitor has minimal VRR flicker, and most people won't notice it, even with changing frame rates.

This monitor uses pulse width modulation (PWM) at all brightness levels, though it's at such a high frequency that you don't notice it.

This monitor has two layers of oscillation: a 4,000Hz PWM frequency nested within a 200Hz backlight partial-dimming frequency. The slower 200Hz frequency doesn't dim very much each cycle, as you can see in our partial-dimming oscilloscope graph. The full PWM flicker itself happens at 4,000Hz, as you can see in our PWM flicker oscilloscope graph. So while it technically flickers, the effect is unnoticeable, which is why we term it "Flicker-Free".

The BenQ EX321UX has low input lag for a responsive feel.

This monitor doesn't display a 1440p @ 120Hz signal from the Xbox Series X|S, even using the console's override function. However, while 1440p @ 60Hz required the override function, it did work.

The Xbox Series X|S only supports HDR with 4k signals, so this isn't a limitation of the monitor.

The HDMI3 port doubles as an ARC/eARC port, allowing digital audio passthrough to compatible devices such as soundbars and receivers. The included remote can be used to adjust the audio device's volume.

The USB-C port on the underside of the monitor provides up to 6.9W of power.

The BenQ MOBIUZ EX321UX works well with macOS. VRR works well, and HDR looks good with certain Color Mode settings. 'Sci-fi' looks most accurate over USB-C, though 'Cinema' also looks good despite being too dark. Additionally, the default 'Fantasy' Color Mode looks less accurate over HDMI, and 'Display HDR' looks much better.

If you connect the monitor to a MacBook with an HDMI or USB-C cable and the MacBook is plugged in, windows migrate to the monitor when you close the lid. Additionally, they return to their previous position if the MacBook is reopened. This also happens if you connect via USB-C and the MacBook isn't plugged in. 

However, if you connect over HDMI and the MacBook isn't plugged in, the MacBook and monitor go to sleep. When you reopen the MacBook windows resume in their previous position.

Additionally, the KVM works well with macOS.

The BenQ MOBIUZ EX321UX has several extra features, including a KVM switch, which allows you to switch between two computers while using the same peripherals. It takes about five seconds to switch between devices, which you can do using the input button on the monitor or the remote. It also has several extra features, including:

• Low Blue Light: Decreases the blue light from the display. You can learn more about this in our blue light filters article.
• Shadow Phage: Adjusts contrast in real-time to optimize detail presentation.
• Brightness Intelligence: Uses an integrated light sensor to adjust brightness and contrast.
• Light Tuner: Increases the brightness of dark shadows for better visibility.

You can learn more about the monitor's settings in the user manual.