Gaming Performance

The Viotek GNV34DBE2 sports a 144 Hz refresh rate VA panel, which supports adaptive synchronization technology for both AMD and NVIDIA graphics cards. The adaptive synchronization range is 48–144 Hz, so that's the framerate range your PC needs to achieve at 3440x1440 for you to experience buttery smooth, screen tear-free gameplay. The adaptive synchronization technology is turned off by default, which is one of many weird choices Viotek made when setting up this monitor. With that in mind, if you want to use it, you first have to venture into the OSD's Main Menu, then scroll down to Other, and then switch the "Adaptive-Sync" option from Off to On.

Response Time and Overdrive

The Viotek GNV34DBE2 has a 6 ms GtG response time. The panel uses overdrive technology to make the pixel transitions faster, and you will find the option under "Response Time" in the OSD (Main Menu > Picture Quality Settings > Response Time). Response Time has a total of four settings: Off, Low, Middle, and High.


I extensively tested all of them by using the so-called pursuit camera method developed by the good people of Blur Busters, namely Mark D. Rejhon. The idea of the procedure is to use a standard DSRL camera to capture the motion blur exactly like your eyes see it. That's achieved by mounting the camera on a smooth slider, setting the camera exposure to four times the length of the monitor refresh rate, and loading the Ghosting Test Pattern with the Pursuit Camera Sync Track, invented by Mark Rejhon of Blur Busters. The camera then has to be slid sideways at the same speed as on-screen motion. The synchronization track is there to tell you if you're moving the camera too fast or too slow, or if it shakes too much. The procedure takes some practice and getting used to, but yields great results and lets us examine the differences between various overdrive settings at various monitor refresh rates.

I made a series of photos at 60, 100, 120, and 144 Hz with all four available Response Time settings. Let's look at the results and figure out what the ideal overdrive setting would be:



Setting the Response Time to "High" results in the clearest reproduction of moving objects but it can cause some overshoot in extreme situations (quickly scrolling through a bright website, for example). Because of that, I suggest sticking with the "Middle" setting, which is only slightly worse at high framerates, and looks better at lower refresh rates (60 Hz).

Moving Picture Response Time (MPRT)

In the OSD, the Viotek GNV34DBE2 also offers the "MPRT" toggle. If you turn it on, the backlight will start strobing to achieve a "1 millisecond-like" response time at the expense of picture brightness and other strobing-related issues, such as flickering and crosstalk. The "1 ms MPRT" response time is not to be confused with 1 ms GtG response time, as the commonly used GtG value tells us how much time it takes for a pixel to change between two colors, while the MPRT (also known as display persistence) represents how long a pixel is continuously visible for. It's important to know that the MPRT isn't a blur reduction technology, but a measurement, which can be lowered by backlight strobing. Viotek, along with many other monitor manufacturers, inappropriately uses the "MPRT" name for a blur reduction setting. I don't see this as a big issue as long as you're aware of the difference. Here's a comparison of moving object sharpness with the MPRT toggle off and on.



Activating the MPRT toggle results in the sharpest possible moving visuals the Viotek GNV34DBE2 has to offer, but it locks the picture brightness at 148 cd/m², which isn't unusable, but far lower than what I'd deem acceptable for combined daytime and nighttime usage. In other words, keep the MPRT toggle off; even though moving objects will be slightly blurrier, you'll have a wide brightness range at your disposal.

Input Lag

To measure the input lag of a monitor, I've switched from using the high-speed camera method to a new tool: the NVIDIA LDAT v2, which I've covered extensively in my NVIDIA Reflex review.

The LDAT (Latency Display Analysis Tool) is a small device that is strapped onto a monitor, measures brightness changes, and provides us with end-to-end system latency data—the so-called mouse to photon latency. Using it for reliable and repeatable monitor input lag testing was made possible by NVIDIA's inclusion of the flash indicator feature in some Reflex-supported games. The flash indicator is essentially a white box, displayed at the left edge of the screen at the moment when a mouse click "arrives" to the screen. I simply place the LDAT sensor on the part of the screen where the flash indicator will appear and click the mouse button on the sensor itself. The sensor will then detect the sudden change in brightness and calculate how much time it took between the mouse button click and the flash appearing on the screen—that's the aforementioned end-to-end system latency. While this method doesn't let me isolate the input lag of the monitor as the only measured value (the high-speed camera method didn't do that either), if the rest of my system remains unchanged, the tested monitors can be compared to each other.

One other excellent characteristic of the LDAT method is the Auto Fire feature of the LDAT software. The Auto Fire feature allows me to select a number of "shots" (test iterations) as well as the "shot delay" (a delay between mouse clicks). All I have to do is run the desired game, align the LDAT sensor to the flash indicator area, and press the "mouse" button on the LDAT. The sensor and accompanying software take care of everything else. Less than a minute later, I have my test results—the minimum, average and maximum measured end-to-end system latency and the standard deviation.

The game I'm using for monitor input lag testing is Overwatch for several reasons. It has an integrated 400 FPS framerate limit, which my test system has no trouble hitting and maintaining at low settings at any given resolution. By keeping the framerate at 400 FPS, I'm maintaining a low and constant GPU render latency (around 2 ms). Overwatch also has an easily accessible practice range, which allows me to do all of my tests in a controlled environment. Finally, its game engine detects inputs even when a gun is reloading, meaning I don't have to worry about character selection or their ammo magazine size—once I trigger the Auto Fire feature, the test will run in 100 iterations regardless of what's happening in the game. My tests are conducted with the NVIDIA Reflex technology turned off (at 400 FPS, it wouldn't make any difference to system latency anyway), with adaptive refresh rate technologies (G-Sync, FreeSync, VRR) deactivated and V-Sync off.


In the end, we get the so-called button-to-pixel lag—the time that passes from the moment you do an action with your mouse until said action is first registered on the screen. Anything below 16 ms (that equals one frame of lag at 60 Hz) can be considered gaming-grade, and such a monitor is suitable even for the most demanding gamers and esports professionals. If the input lag falls between 16–32 ms (between 1–2 frames of lag at 60 Hz), the monitor is suitable for almost everyone but the most hardcore gamers, especially if they're playing first-person shooters on a professional level. Finally, if a monitor's input lag is higher than 32 ms (over 2 frames of lag at 60 Hz), even casual gamers should be able to notice it. Will they be bothered by it? Not necessarily, but I can't recommend a screen like that for serious gaming.

Here's how the Viotek GNV34DBE2 holds up in terms of input lag.



After doing 100 iterations of the LDAT-powered input lag test, the Viotek GNV34DBE2 showed an average input lag of only 11.7 milliseconds, which means it's responsive enough even for the most demanding gamer.