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VRR monitors are becoming ubiquitous, now VESA’s certification will make them good

VESA, the computer display organization behind standards such as the DisplayPort interface, has a new certification program designed to help customers find better monitors with variable refresh rates. Unlike its previous HDR certification program, which measured things like maximum brightness, the new Adaptive-Sync Display Compliance Test Specification (or Adaptive-Sync Display CTS) is designed specifically for variable refresh rate monitors that look like flicker and error errors. lost frames.

Variable Refresh Rate (VRR) is a technology that enables a monitor to synchronize its refresh rate to the output of any device connected to it, reducing the occurrence of visual artifacts, screen tearing, and image stimulation issues. When VRR support first began to appear on graphics cards and monitors, it tended to be tied to specific manufacturers: G-Sync for Nvidia and FreeSync for AMD. But in 2014, VESA built native Adaptive-Sync support into DisplayPort 1.2a based on technology provided by AMD, and now it’s a standard that is cross – compatible with graphics processors from all three major manufacturers: IntelAMD and Nvidia.

Both Nvidia and AMD have long offered their own certification schemes for VRR monitors using their proprietary standards, but it’s more of a wild west when it comes to the open Adaptive-Sync standard. When Nvidia started testing Adaptive-Sync monitors back in 2019 as part of their “G-Sync Compatible” initiative, only 5.56 percent of the models tested passed. They either did not offer a wide enough range of refresh rates or had other image quality issues such as flicker.

VESA’s new certification is designed to offer similar assurances about a screen or laptop’s Adaptive-Sync support. But unlike Nvidia or AMD’s certifications, it’s an open source industry standard, and its testing criteria are public.

“Obviously there are proprietary standards from GPU vendors, but they have never revealed the full scope of their testing,” said Roland Wooster, Intel engineer and chairman of the VESA task force that came up with its new test, over a Zoom call . . For example, look at Nvidia’s website and you’ll see that it says a monitor needs to go through over 300 tests to earn itself a G-Sync logo, but it’s less outstanding about exactly what those tests are. And it’s created a lot of confusion over the years, especially when it comes to criteria like “Lifelike HDR.”

With its certification, VESA tests raw Adaptive-Sync performance instead of GPU-specific standards like FreeSync or G-Sync. For this reason, VESA expects their certification logos to be often associated with manufacturer-specific equivalents. A G-Sync logo tells you how a monitor will perform with an Nvidia GPU, but a VESA AdaptiveSync logo can tell you how a monitor will work with any Adaptive-Sync compatible source.

Importantly, VESA’s Adaptive-Sync technology is only available for its own DisplayPort standard, which is used across monitors and laptops (including when transferring video via USB-C). Unfortunately, this will not help you pick one of the growing number of TVs that offer VRR support via HDMI 2.1, where standards are even more of a wild west.

But in addition to being more public, Wooster suggests that VESA’s new certification standard keeps screens to a higher standard than these vendor-specific certifications. “We’ve seen some screens that have met the certifications that have flickered, that have jitter, and that do not meet the gray-to-gray specifications that we have here,” he says. In a follow-up email, he tells me that he expects significantly less than half of the Adaptive-Sync monitors on the market to meet VESA’s standards, similar to what Nvidia found when it introduced its own Adaptive Sync certification. Sync screens.

Under VESA certification, there are two compliance logos that monitors can serve. MediaSync is intended for monitors that you can use to watch videos or use to create content, while AdaptiveSync is aimed at game monitors. If their device passes these tests, manufacturers are allowed to patch the relevant logos across the product box, website or where they think potential customers may see it. A screen that does not pass the tests cannot use the logo, but the manufacturers do not have to publish an error.

The MediaSync logo, focused on video playback.
Image: VESA

The AdaptiveSync logo is intended for game screens.
Image: VESA

The first of the two logos is called MediaSync. The focus here is on ensuring that monitors are capable of playing video content – with less than 1 ms jitter – at each of the 10 major international frame rate standards (23,976, 24, 25, 29,97, 30, 47,952, 48, 50, 59 , 94 and 60 fps – where 23,976 have often been typical of movie content in America). It sounds like a simple question, but 24fps content can have real problems when playing on 60Hz screens because the images do not split evenly in the screen refresh rate. Three-to-pull down was a common way of dealing with the problem (where the first frame appears twice, the second three times, the third twice, and so on), but it can create unpleasant shakes. A MediaSync logo means that a monitor can use Adaptive-Sync to avoid such issues.

The second is the AdaptiveSync logo, which is aimed at high-refresh game monitors. So to begin with, a screen with an AdaptiveSync logo should be able to run at a maximum refresh rate of 144Hz or more at natural resolution in factory setting mode, and its adaptive refresh rate should be able to go down to 60Hz. It may not seem like a very low floor, but Wooster explains that if your frame rate drops lower, to e.g. 58 fps, then a monitor is expected to use frame doubling to bring it up to 116 fps and bring it back to its adaptive sync range.

If a monitor can reach 144Hz, then you will see a “Display 144” box to the right of the certification logo, but Wooster tells me that this number will reflect whatever a monitor’s maximum refresh rate is – whether it’s 144, 240 or 360Hz – at native resolution.

It’s just not enough to be able to display this range of frame rates. To be certified, a monitor must be able to do well. This does not mean showing a level of flicker that is visible to the naked eye, even when the screen speed of a screen changes rapidly. This does not mean losing frames – which can happen when a monitor provides input with support for higher frame rates than a panel actually supports.

VESA also takes a detailed approach to how it measures response time, or the time it takes for a screen pixel to refresh. Across the industry, it is common to see this expressed as a “gray to gray” response time, or approximately the time it takes for a pixel to switch from one grayscale to another. If response times are too slow, screens may exhibit “ghosting” where the remnants of a previous image are still visible on a screen while pixels struggle to keep up. To get an AdaptiveSync logo, a monitor must have a response time of less than 5ms.

5ms may seem high compared to the 1ms response times that many manufacturers claim their monitors are capable of. But in real tests, like those performed by Rtingsresponse times are generally much higher than 1 ms. Rtings generally classifies any response time of less than 6ms as a “good value”.

Manufacturers like to make these claims about 1 ms response times because they are not as strict with their testing as independent reviewers like Rtings or VESA’s test centers. Some manufacturers, Wooster says, can make a number of gray-to-gray changes and then choose the best result. Others may benefit from the fact that a hotter panel can react significantly faster than a cold one. Overdrive can be used to achieve a faster response time on paper, but at the expense of ugly visual artifacts.

VESA’s solution is to measure a variety of gray-to-gray transitions (20 in total) and to take an average instead of choosing the best result. Tests are performed with an ambient temperature of between 22.5 and 24.5 degrees Celsius (72.5 – 76 Fahrenheit). Monitors are given time to reach a stable temperature first, and limits are set on how much over- and under-swing a monitor is capable of showing and still passing.

Wooster declined to say how many VESA members he expects to pay for their devices eventually becoming MediaSync or AdaptiveSync certified (the fee is the same whether a monitor exists or fails), but the first certified monitors should appear on VESA’s website from today. He points to the number of devices currently carrying one of VESA’s HDR certifications as an example of the amount of monitors and laptops we’ll eventually see carrying the new AdaptiveSync logos.

Given VESA’s formidable list of members from across the display industry, these little orange and blue logos can quickly become a significant quality brand when you buy your next monitor or laptop.

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