In every CNET TV review, I compare three or more similar TVs side by side in a dedicated, light-controlled test lab. For each review, I use a rigorous, unbiased evaluation process that has been shaped by over twenty TV reviews. I test TVs with a combination of scientific ratings and actual testing of TV, movie and game content.
To make sure I can check the picture quality of every TV, I connect each one to an AVPro Connect 8×8 4K HDR splitter so that each one receives the same signal. I test TVs using various lighting conditions, playing different media, including 4K HDR movies and console games, in all different test categories, from color to video processing to playback to HDR.
To rate each TV, I use special equipment to rank them according to light output and color. My hardware includes a Konica Minolta CS-2000 spectroradiometer and a Murideo Six-G 4K HDR signal generator. I use Portrait Displays CalMan Ultimate software to test every TV I review in terms of brightness, black levels and color.
The Leo Bodnar Lag Tester samples three regions of the screen for lag, and these are averaged to give a score for each TV.
I play various games from Xbox Series X or PlayStation 5, and note the effects of game modes and settings as well as 4K/120Hz and VRR input capabilities. Helpfully, Xbox includes a 4K/120Hz and HDR compatibility test: Settings>TV and display options>4K TV details. The page will detail the HDR modes it supports (including Dolby Atmos) and whether it will support VRR — if the TV ticks all the boxes then it has the best compatibility with high-end Xbox games.
Our review covers things like features, design, smart TV performance, connectivity including HDMI input and gaming compatibility.
Measuring input lag (in milliseconds) is an important aspect of my testing process for gaming TVs.
See the How CNET Tests TVs page for more details.
Input lag will generally be lower in game mode than any other mode on your TV. Here are a few more game-specific features I looked at on each TV.
How to turn on game mode. In most cases, viewing in game mode is not automatic, so you will have to turn it on manually, and sometimes the game monitor settings can be difficult to find. Many use a picture mode called “Game” while others, like Samsung and Vizio, allow you to use game mode at any setting.
The game mode makes a difference, but not the frequencies at all. As you can see from the table above, most TVs significantly reduce lag when you turn on game mode, but many do not. In general, expensive TVs with detailed video processing get more benefit when you include game mode. Additionally, and as I mentioned above, the Boost mode on LG OLEDs only works at 60Hz and not 120Hz.
Most TV game modes are good enough for most gamers. No matter how nervous you are, it will be it’s hard to tell the difference between 10 and 30 milliseconds of input lag. Most gamers won’t even be able to tell the difference between turning game mode on and off — it all depends on the game and your sensitivity to lag.
Turning on the game mode can damage the image quality (slightly). TV manufacturer menus often refer to reduced picture quality. A reduction in image quality is often the result of disabling video processing. In my experience, however, the difference in image quality is really subtle with console games, and it’s worth the trade-off if you want to reduce lag for a better gaming experience.
4K HDR playback lag is different from 1080p. The resolution of the display you’re playing on has an effect, too, as newer consoles are noticeably brighter 4K HDR gaming output, I started testing 4K HDR lag in 2018. In general, the numbers are similar to lag with standard 1080p resolution, but as you can see in the chart above, there are exceptions.
Testing is an exact science. I use Leo Bodnar lag testers. Here’s how they work, and how I use them. I use two of these Bodnar lag testers — one for 1080p and one for 4K HDR — which use onboard optical sensors to measure and report input lag. When connected to an HDMI port, Bodnars makes the screen light up at three different points and places the unit’s on-board light sensor on the screen at these points. Calculate the lag at each point and average the three readings to get a score. You may see different lag test results in different review shops, which may use Bodnar or another method.
