OLED monitor KTC G42P5 in review: 4K gaming on huge 42-inch OLED

From the front, you only look at a 42-inch glass panel. You won't find any thick, black plastic display edges — the extra-thin side bezels are also made of glass.

The rear is dominated by a white painted steel sheet, which protects the screen well on the one hand but also contributes to the impressive weight of 15 kg (without the stand). The display technology sits between the glass front and the steel sheet at the back, framed in a black plastic border that seems quite thick.

The stand is conspicuous, which provides good stability due to its considerable weight and sheer width, but it also takes up space. However, the stand doesn't take up much depth. If you turn on the monitor via remote control, you'll notice the LED lighting on the stand, which also changes color periodically.

The base allows the G42P5 to be tilted and even rotated a bit, which means it can still be aligned straight even in suboptimal standing conditions. On the other hand, there is no height adjustment. Thus, the monitor stands quite high on a normal desk.

The connection panel is located on the back on the left side and is slightly indented towards the center. The ports are easy to reach due to the lateral exit. The required cable length is a bit longer, since the cables have to be routed around the side or downwards around the monitor first. Optionally, a sheet metal cover is included to cover the ports.

The table above shows all available connections. One practical feature is the presence of a USB Type-C port with 90 W Power Delivery. Thus, it is also possible to charge the connected laptop simultaneously. The integrated KVM switch ensures that several PCs or laptops can be controlled.

All said, the HDMI 2.1 ports do not provide the full 48 GBit/s bandwidth but instead are limited to 24 Gbit/s. Thus, 10-bit 4:4:4 chroma subsampling only works via a PC using Display Stream Compression (DSC) lossless compression, whereas consoles only get to output 10-bit 4:2:0.

KTC has installed a single joystick at the bottom center to control the OSD. Thanks to the good pressure actuation, the monitor's menu can be controlled easily, but it is even more convenient with the included remote control — something that is not often found on gaming monitors.

A circular quick menu gives quick access to the most important settings. The complete options are available via the main menu, which is also controlled by the remote. Here we set the usual parameters like brightness and contrast along with pther parameters like the KVM switch, the overclocking function (138 Hz), and more. A crosshair or FPS viewer can also be displayed.

LG's panel has a thin, matte surface that is supposed to prevent reflections during gaming. Reflective surfaces usually have even more brilliant colors, which should hardly be a problem for the OLED.

We set the brightness to 100% and measured a peak brightness of almost 450 nits, which corresponds to the manufacturer's specifications. Unfortunately, the illumination cannot really be checked due to the aggressive Automatic Brightness Limiter (ABL). Every measurement, as a result, shows a slightly different value, so we measured the brightness without it. Subjectively, the OLED shines quite evenly.

However, you have to keep in mind that this peak brightness can only be achieved in small zones but not over the entire screen surface. For example, if the display shows a completely white full screen, the brightness is turned down considerably to protect the panel (ABL). A smaller measurement area must therefore be selected.

In standard mode, i.e., at a brightness of 35%, we only measured just over 150 nits.

The response times of less than 1 ms are beyond any doubt. The screen flickers with 60 Hz or 120 Hz, which is typical for OLEDs.

The KTC G42P5 impresses as a gaming monitor especially with its OLED virtues and sheer size. An affordable gaming monitor with OLED technology in 42 inches is not really commonplace. Colors, black levels, and contrasts are convincing. Response times and the 138 Hz overdrive mode are also impressive for gamers. With a little user tuning, a higher accuracy can be eked out of the OLED.

The uncalibrated Display P3 mode and the mediocre speakers beget some criticism. KTC would be happy to add the full HDMI bandwidth via a firmware update. In office mode with large, bright images, the monitor is dimmed for protection.

The KTC G42P5 is a large, colorful, and high-contrast OLED monitor with many gaming features and is thus suitable for gamers who like to play games on a large screen in great quality.