Bottom Line
The KTC H34S18S is an affordable 34″ 3440×1440 165Hz ultrawide curved gaming monitor based on a VA panel with a high contrast ratio and plenty of useful features. It also offers a wide color gamut and excellent overdrive implementation, which is impressive for this price range and why we highly recommend it.
The KTC H34S18S is yet another affordable 34″ 3440×1440 165Hz ultrawide curved gaming monitor with a VA panel – let’s see how it performs in our tests!
Image Quality
There are over 50 monitors based on the 34″ 3440×1440 144Hz VA panel, so picking the model best suited to your preferences and budget can be difficult. The reason this form factor is popular is due to its excellent value for the price.
You get a big curved screen with a high resolution for sharp details, while the ultrawide format provides a more immersive viewing experience with a wider field of view in compatible games and extra horizontal screen space for office-related work.
Moreover, the VA panel offers a high contrast ratio for deep blacks, vivid colors and decent viewing angles, while the high refresh rate ensures a huge boost in motion clarity in comparison to the standard 60-75Hz displays – all that at an alluring price.
The initial 34″ 3440×1440 144Hz VA models were based on Samsung’s panels.
However, since then, Samsung sold their LCD fabs to TCL/CSOT, so the KTC H34S18S is based on the newer SG3402H03-1 VA panel. Some improvements to the panel include a slight 165Hz factory-overclocked refresh rate and a boost in static contrast ratio to 4,000:1 (from 3,000:1).
KTC also pairs the panel with a custom backlight for a wider color gamut, fine-tuned pixel response time overdrive and MBR (Motion Blur Reduction) implementation while maintaining competitive pricing, making for a promising all-around option, so let’s put it to the test.
We’re using the Datacolor SpyderX Pro colorimeter paired with DisplayCAL and ColorHCFR software for our tests.
First, we’ll have a look at the image accuracy out of the box when it comes to color deviance, color temperature and gamma. By default, the KTC H34S18S uses the ‘User‘ preset with the ‘Normal‘ color temperature mode of 8373K measured, which gives the whitepoint a noticeable bluish tint (target is 6500K).
However, simply changing the color temperature mode to ‘User‘ improves it to 7223K, which is also a bit colder than ideal but the bluish tint is now almost completely gone.
It also allows for a higher 353-nits peak brightness instead of 302-nits of the ‘Normal’ mode.
The monitor has several presets (Standard, User, Movie, Photo, RTS, FPS1 and FPS2) but these just have different brightness, contrast and other settings pre-defined and locked.
Therefore, we recommend using the default User mode and User color temperature mode as they offer the most accurate results as well as full adjustability.
Next, gamma tracking of the default Gamma 2.2 mode is decent with an average of 2.09 (target is 2.2), meaning that most scenes will be slightly brighter than intended.
In the OSD (On-Screen Display) menu, you can change the gamma from the default 2.2 to 2.4, which will give you a higher gamma average of 2.29. This will cause all scenes to be slightly darker than intended, but both options are fairly close to the target, so you can pick according to your personal preference.
Finally, since the monitor has a wide color gamut, regular sRGB SDR content will be over-saturated. For gaming, watching videos and everyday use, most users will prefer the extra color vibrancy anyway – and with an sRGB color volume of 131.6% and 90.6% DCI-P3 color space coverage, the over-saturation is not too overblown.
It’s worth noting that we measured a lower DCI-P3 color space coverage than the specified 98%, but the display has a higher sRGB volume than the specified 123%.
This can be caused by using different color standards, testing methods and equipment. The colors are vivid overall and we noticed a tad of extra vibrancy in comparison to the more common ~125% sRGB wide gamut displays.
This also results in a Delta E of 2.59 average (target is ≤ 1.5) and 5.6 maximum (target is ≤ 3).
Sadly, there is no sRGB emulation mode that would restrict the color gamut to ~100% sRGB in monitor OSD settings. Using AMD’s Custom Color software solution over DisplayPort resulted in a too-low color temperature of ~5000K without a properly clamped gamut (~125% sRGB).
Using an NVIDIA GPU over DisplayPort with the novideo_srgb third-party tool for color gamut clamping, we also got only partially clamped gamut to 125% sRGB, though without the color temperature drop.
When the monitor is connected via HDMI, the software clamp works as intended on both AMD and NVIDIA GPUs, restricting the gamut down to ~102% sRGB, which improved the average Delta E to 1.52 and maximum Delta E to 3.4.
So, if you plan on doing professional color-critical work in sRGB color space, you will need a colorimeter to profile the display. However, in this case, you should be considering a more expensive IPS model anyway due to its superior color consistency and wider viewing angles. Alternatively, you can use HDMI, but in this case, you’ll be limited to a lower refresh rate (100Hz) due to bandwidth restrictions.
Another option (if you have an NVIDIA GPU and want to use DisplayPort) is to use our ICC profile linked below with the novideo_srgb tool, given that our gamma corrections match your particular unit of the monitor.
As we mentioned earlier, this is a non-issue for everyday use (gaming, watching videos, web browsing, basic content creation, etc.), since most users will prefer the extra color vibrancy.
While VA monitors have 178° wide viewing angles specified just like IPS panels, some minor gamma and saturation shifts can be observed on VA displays. Again, this isn’t that noticeable in everyday use or an issue for basic content creation, but it is a concern for professional color-critical work.
After full calibration, the average gamma is close to ideal at 2.18, the average Delta E is reduced to 0.36, and the maximum Delta E is down to 1.08. In the User color temperature mode, we reduced the blue color channel to 47 and left red and green at the default 50 to get the 6518K color temperature.
You can download our ICC profile here. We used a brightness setting of 29/100 for 120-nits.
Next, we measured a maximum brightness of 353-nits, so the monitor can get more than bright enough under normal lighting conditions.
It also has a very low minimum brightness of just 18-nits, which is great for those who prefer low brightness levels when using the screen in a dark room.
We also measured a high 3942:1 contrast ratio at ~200-nits, meaning that the KTC H34S18S display is capable of producing deep blacks.
The 3440×1440 UltraWide Quad HD screen resolution results in a high pixel density of 109.68 PPI (pixels per inch) on the 34″ sized screen of the monitor.
In other words, you get plenty of screen real estate with sharp details and text without any scaling necessary. The resolution is a bit more demanding than 2560×1440, but still not nearly as taxing on the GPU as 4K UHD, allowing for higher frame rates.
The ultrawide aspect ratio provides you with a wider field of view in compatible games. Most games support 21:9 resolution natively, though in some titles you may need to use mods or tinker with some settings for proper support.
Note that there are games with native 21:9 support that may still show in-game cutscenes as 16:9 with black bars at the sides of the image. There’s a quick and easy fix for this using a free HEX editor, such as HxD (link to the official website).
How to fix black bars in cutscenes on ultrawide monitors?
Download HxD, drag and drop the .exe game file to it, go to ‘Replace…‘, select the ‘Hex-values‘ tab, put ‘39 8E E3 3F‘ in the ‘Search for‘ box, and ‘8E E3 18 40‘ in the ‘Replace with‘ box, select ‘All‘ for search direction, ‘Replace All‘ and ‘Save‘. The program will automatically create a backup .exe file as well.
If you have an ultrawide monitor with a different resolution, you’ll need to put a different hex code in the ‘Replace with’ box depending on the exact aspect ratio:
2560x1080 (2.37:1) - 26 B4 17 40
5120x2160 (2.37:1) - 26 B4 17 40
3440x1440 (2.38:1) - 8E E3 18 40
3840x1600 (2.4:1) - 9A 99 19 40
5120x1440 (32:9) - 39 8E 63 40
7680x2160 (32:9) - 39 8E 63 40
You can also use the Flawless Widescreen application, which can automatically fix ultrawide resolutions in most games.
Note that pre-rendered 16:9 cutscenes will still be shown with black bars, but this won’t be as immersion-breaking given that there are only a few of those in most games.
On the other hand, some games purposely don’t support ultrawide resolutions as developers think it would give an unfair advantage over other players. Luckily, there aren’t many such titles, the most popular ones include Valorant and Starcraft 2. Some games, such as Elden Ring and Sekiro will need a 21:9 mod, but will then only work in offline mode.
Of course, when watching 16:9 videos, they will be displayed with black bars at the sides of the screen. You have the option to stretch or zoom in the picture to fill the screen, but this results in worse (or cropped) image quality.
In contrast, videos shot at the cinematic ~21:9 aspect ratios will fill the entire screen without black bars at the top/bottom of the image (as they would be displayed on 16:9 screens).
There are some “21:9 videos” that are just 16:9 videos with black bars added at the top and bottom of the image, usually found on streaming services, such as YouTube and Netflix, which will look like this:
To fix this, you can use Zoom to Fill – UltraWide Video or a similar browser extension to fill the screen without clipping any details or stretching the image.
Finally, the ultrawide aspect ratio is also especially useful for productivity work and audio/video editing due to all the extra horizontal screen space.
Next, we tested brightness uniformity.
The screen is a bit darker in the corners (up to 17%), but this is the case with most displays and it’s not noticeable during everyday use.
We found one dead pixel in the bottom left part of the screen, though it was hard to spot and not noticeable in everyday use.
There was no excessive VA glow or backlight bleeding and no pixel inversion artifacts, image retention or frame skipping.
HDR
The KTC H34S18S also supports HDR (High Dynamic Range), however, while it can accept and display the HDR10 signal, it lacks a full-array local dimming (FALD) solution or an OLED panel for a true HDR viewing experience.
Some HDR content can still benefit from the wide color gamut and 10-bit color depth for smoother gradients, but due to the low brightness and contrast, details in the highlights and shadows of the image will be lost.
We actually measured a lower 320-nits brightness in HDR mode with a too-high 7415K color temperature resulting in a bluish tint to whitepoint, and color settings are locked in the HDR mode, so it cannot be improved.
In order to preserve details and image accuracy, we recommend sticking with the SDR mode on this monitor (and for that matter, all ‘HDR’ monitors without FALD or OLED technology).
Performance
Moving on, the monitor has a 165Hz refresh rate for a smooth gaming experience. The high refresh rate will also make everyday use appear more fluid as just moving your cursor around or scrolling will look much smoother.
For pixel response time speed and input lag testing, we’re using OSRTT. We’re also using Blur Buster’s UFO ghosting test with 960 Pixels Per Sec, shutter speed set to 1/4 of the refresh rate with fixed focus, ISO and color temperature (6500K). Before the tests, the monitor was calibrated and warmed up.
The KTC H34S18S has four response time overdrive modes: Off, Low, Middle and High. The ‘High’ mode is too aggressive as it pushes the pixels to change too fast thus causing overshoot (or inverse ghosting), while the ‘Off’ mode is too slow, which results in noticeable trailing behind fast-moving objects.
If you’re gaming at a fixed 144Hz or 165Hz refresh rate (or your frame rate is constantly within that range when using VRR), you should use the Middle mode. It adds some overshoot, but it significantly improves the pixel response time speed. The amount of tolerable inverse ghosting will vary depending on the game/scene.
The Middle overdrive mode provides you with a fast 3.29ms GtG (gray to gray) average pixel transition speed and an impressive 93.33% refresh rate compliance, though it comes at the cost of moderate overshoot with an average error rate of 15.17%.
While pixel overshoot artifacts can be observed in everyday desktop use and in the UFO ghosting tests we’ll get into below, we haven’t actually encountered any while gaming.
As you can see, the 0 up to 51 RGB transitions are still high at 11ms (almost double the 6.06ms refresh rate cycle of 165Hz), but the only ghosting-related issues we noticed in games are the flickering-like artifacts caused by too strong sharpening filters (which can be disabled in most games).
You can also use the Black Equalize option from the OSD menu to improve response time performance. Increasing this setting will raise black levels, so dark transitions will be faster (but blacks won’t be as deep).
So, while the KTC H34S18S is not as fast as the fastest LCD gaming monitors, it is notably faster than the typical VA gaming displays and we find that most gamers will be satisfied with the response time performance.
Keep in mind that while the KTC H34S18S has a faster average response time speed than the KTC H24T09P and H27T22 models in the chart above – these two monitors use IPS panels with significantly faster black to dark-gray pixel transitions (~2ms from 0 to 51 RGB, as opposed to 11ms of the H34S8S), so they don’t suffer from the above-mentioned visual artifacts, but they also have lower contrast ratio.
For gaming at lower refresh rates (or lower than 144FPS when using VRR), we recommend using the Low mode as it offers the best results across the entire refresh rate range.
The average response time speed is reduced to 5.93ms, but you also get less overshoot with a 2.54% average error rate, whereas Middle has way too much overshoot at refresh rates below 120Hz.
Variable refresh rate (VRR, Adaptive-Sync, AMD FreeSync, NVIDIA G-SYNC Compatible) is supported with a 48-165Hz dynamic range.
This technology synchronizes the monitor’s refresh rate to the GPU’s frame rate, so at 75FPS, for instance, it will change to 75Hz to prevent screen tearing without adding any latency (as V-SYNC would). This is why the Low overdrive mode is best for VRR gaming as it won’t add overshoot at low refresh rates.
Below 48Hz/FPS, LFC (Low Framerate Compensation) is triggered, which makes the display show multiples of the framerate (47Hz -> 94FPS, for instance) to keep tearing at bay, though in our tests, it was usually triggered at around 54Hz.
To enable VRR, you must first enable the FreeSync/G-Sync option in the OSD menu, and then enable Adaptive-Sync or G-SYNC Compatible in your GPU drivers settings.
While the monitor is not officially certified by AMD or NVIDIA, VRR works on all supported cards (GeForce 10-series or newer over DisplayPort, Radeon 200-series or newer over both HDMI and DP).
Sadly, the VRR brightness flickering issue is noticeable in games with heavily fluctuating frame rates and in some in-game menus and loading screens, but this is common for high refresh rate VA and OLED panel displays.
Since screen tearing is not that noticeable at 165Hz (at least in comparison to 60-75Hz), you should simply disable VRR in the affected games or use V-Sync instead.
There’s an additional VRR option in the OSD menu called ‘Limited’. It doesn’t affect the VRR range as we assumed but rather locks the overdrive mode selection at 165Hz and offers a response time performance between that of ‘Off’ and ‘Low’, so we don’t recommend using this option.
To sum up, we recommend Middle overdrive for 144Hz – 165Hz, and Low for 60Hz – 120Hz.
Finally, here’s how these pixel response time transitions look in Blur Busters’ UFO ghosting tests. As we mentioned, while the Middle overdrive mode has noticeable overshoot at 165Hz, we didn’t detect it in real-world gaming (though it’s visible on the desktop when moving application windows around). At 120Hz and lower refresh rates, Middle has too much overshoot and Low looks much better.
Here’s how the KTC H34S18S compares to a slower VA, fast IPS, higher refresh rate OLED and TN panels and a monitor at 60Hz.
Next, the KTC H34S18S also supports MBR (Motion Blur Reduction). By enabling MPRT in the OSD menu, the display uses backlight strobing to reduce the perceived motion blur at the cost of image brightness.
At 165Hz, the brightness is reduced to 81-nits, which might be too dim for some users (88-nits at 144Hz, 90-nits at 120Hz, 95-nits at 100Hz).
Further, MBR can only be enabled at a fixed refresh rate (100Hz minimum), so it cannot work at the same time as VRR on this monitor. It also introduces screen flickering that’s invisible to the human eye but can cause eye strain after prolonged use to sensitive users.
With MBR disabled, the monitor is flicker-free as it uses DC dimming and you can also find a low-blue light filter in the OSD menu.
As you can see, MPRT reduces motion blur but it still has some strobe crosstalk (the image duplication effect), which is most noticeable on the upper and center part of the screen.
Ideally, the image should be clear across the entire screen or at least be the clearest in the center, though some gamers might still find this feature useful in fast-paced games. For the best results, your frame rate should match the refresh rate, so if you can only maintain 120FPS, for instance, lower the refresh rate to 120Hz as well.
Lastly, here’s a look at the display latency performance.
The measured display latency is low and amounts to 4.08ms at 165Hz, 4.87ms at 120Hz and 8.22ms at 60Hz.
As the latency is lower than the refresh rate cycle, this means that you won’t be able to notice or feel any delay between your actions and the result on the screen.
Features
At the rear of the screen, there’s a directional joystick for quick and easy navigation through the OSD menu. It also serves as a power on/off button by holding it for 3 seconds to turn it off, or short-press to turn it on.
Pushing the joystick to the side opens up shortcuts to certain functions: left for Game Plus features (Timer, Crosshair, FPS Counter), up for input selection, right for picture presets and down for brightness.
Besides the standard image adjustment tools (brightness, contrast and color temperature), the KTC H34S18S also offers some advanced settings, including hue/saturation, aspect ratio (full, 16:9 and 4:3 – can’t be changed when VRR is enabled), sharpness, gamma (1.8, 2.0, 2.2/off and 2.4), DCR (dynamic contrast ratio, recommended setting: Off) and automatic input detection.
Other useful features include Black Equalizer (improves visibility in dark scenes by altering the gamma curvature), crosshair overlays, on-screen timers, a refresh rate tracker, Picture in Picture / Picture by Picture, audio volume (for the connected headphones or external speakers) and OSD-related settings, such as language, position, reset, timeout and transparency.
While KTC doesn’t offer a dedicated desktop application for OSD adjustments, it does support DDC/CI, so you can use third-party applications, such as ControlMyMonitor or ClickMonitorDDC, to adjust monitor settings using your mouse/keyboard.
The monitor also supports firmware updates via USB. All our tests were done on the “USA-1.0.1” firmware.
Design & Connectivity
The KTC H34S18S has a sturdy metal stand with a good range of ergonomics, including up to 90mm height adjustment, -5°/20° tilt, +/- 20° swivel, +/- 5° pivot and 100x100mm VESA mount compatibility (8mm length M4 screws recommended).
The screen has a moderate 1500R curvature for added immersion and a light (25%) low-haze matte anti-glare coating that prevents reflections without making the image too grainy.
Next, the monitor has ~2mm ultra-thin bezels at the top and at the sides with a ~6mm black border before the image starts, while the bottom bezel is a bit thicker at ~12mm with a ~2mm black border.
The design is fully textured/matte with a subtle circular red accent at the bottom of the stand riser.
There are ventilation holes at the top of the screen, a cable management bracket, a magnetic cover for inputs and RGB LEDs at the rear of the monitor that gradually cycle through red, green, blue, yellow, cyan and magenta colors – it can also be disabled.
On the bottom bezel, there’s a blue LED power indicator that switches to red (blinking) when the screen’s on standby. The LED power indicator cannot be disabled but it’s not intrusive.
Connectivity options include two DisplayPort 1.4 inputs, two HDMI 2.0 ports (limited to 100Hz at 3440×1440 – or 120Hz at 2560×1440 and 2560×1080), a headphone jack, a USB port for service/firmware updates and an external power supply.
Note that DisplayPort 1.4 is limited to 144Hz with dithered 10-bit color depth, so you’ll need to use 8-bit color for 165Hz. However, this isn’t an issue because most SDR content uses 8-bit color. For HDR, dithering is used for 10-bit color anyway, so it’s also a non-issue.
In the box, along with the monitor and the stand, you’ll also get the required cables (DisplayPort, HDMI, power brick, power cable), a warranty card, a user manual and a screwdriver with three screws for assembling the stand.
Price & Similar Monitors
The KTC H34S18S price amounts to ~$300, but it’s often available with a 10% off coupon on Amazon, bringing the price down to ~$270. It’s available on Amazon and .
Overall, it’s the most affordable 34″ 3440×1440 165Hz ultrawide curved VA gaming monitor with a wide color gamut, so we highly recommend it if you’re interested in this form factor. It’s also one of the fastest models thanks to its well-optimized overdrive.
There’s also the KTC H34S18 variant with a lower 144Hz refresh rate, DisplayHDR 400, RJ45 and USB-C (65W PD), but it’s not available in the US.
You can also find similar 34″ 3440×1440 high refresh rate curved VA models without wide color gamut (99% sRGB specified) at a similar price ($250 – $300):
- Aopen 34HC5CURP
- LG 34GP63A
- LG 34WP60C – tilt-only version of the 34GP63A
There are a few good alternatives with a wide 90% DCI-P3 color gamut available as well:
If you’d rather have an IPS variant, check out the Sceptre E345B-QUN168W and the MSI MAG401QR. However, these go for $300 – $400, have flat screens and suffer from the lower 1,000:1 contrast ratio and IPS glow.
They have more stable VRR performance, wider viewing angles and faster response time, but the image quality is not as immersive. Curved IPS ultrawide models are more expensive, such as the Acer XR343CKP for $500.
In case you want proper HDR support, ultrawide models start at around $800, so you’ll have to settle for a 27″ 1440p 180Hz flat-screen VA variant around this price range – the AOC Q27G3XMN with a 336-zone mini LED FALD backlight.
For competitive FPS games, you should consider a gaming monitor with a higher refresh rate, faster response time and lower resolution. We recommend the ViewSonic XG2431 for under $300 or the HP Omen 27qs 27″ 1440p 240Hz and Dell AW2523HF 25″ 1080p 360Hz models in the $350 – 400$ range.
Finally, if you want a higher resolution display around this price range, check out the MSI MAG274UPF with a 27″ 4K 144Hz IPS panel for $400 as cheaper models have a lower 60Hz refresh rate.
Conclusion
All in all, the KTC H34S18S is an exceptional gaming monitor for the price thanks to its high ultrawide resolution, high contrast ratio and wide color gamut. Moreover, 165Hz ensures smooth gameplay and KTC managed to squeeze excellent pixel response time speed out of this panel with their overdrive implementation.
As expected from this panel technology, some minor ghosting is still noticeable in dark scenes and some games will exhibit brightness oscillations with VRR enabled, so if you’re particularly sensitive to these visual artifacts, consider investing in IPS instead.
Still, we find that most gamers will find these flaws to be tolerable or even negligible, especially after considering the price and the fact that other panels have their inherent drawbacks too.
Specifications
Screen Size | 34-inch |
Screen Curvature | 1500R |
Resolution | 3440×1440 (UWQHD) |
Panel Type | VA |
Aspect Ratio | 21:9 (UltraWide) |
Refresh Rate | 165Hz |
Response Time (GtG) | Not specified |
Motion Blur Reduction | 1ms (MPRT) |
Adaptive-Sync | FreeSync Premium (48-165Hz) |
Ports | 2x DisplayPort 1.4, 2x HDMI 2.0 |
Other Ports | Headphone Jack, USB (for firmware updates) |
Brightness | 350 cd/m² |
Contrast Ratio | 4000:1 (static) |
Colors | 1.07 billion (8-bit + FRC) 98% DCI-P3 specified 90.6% DCI-P3 measured |
HDR | HDR10 |
VESA | Yes (100x100mm) |
The Pros:
- Excellent value for the price
- Immersive image quality with high pixel density, contrast, and wide color gamut
- Plenty of gaming features including VRR and MBR up to 165Hz, PiP/PbP
- Ergonomic stand and rich connectivity options, including dual DP and HDMI ports, audio and USB for firmware updates
The Cons:
- Minor ghosting in dark scenes
- VRR brightness flickering in some games with fluctuating frame rates, in-game menus/loading screens
- No sRGB emulation mode
- DCI-P3 gamut coverage not as wide as specified