VESA, the computer display organization behind standards like the DisplayPort interface, has a new certification program designed to help customers find better variable refresh rate monitors. Unlike previous HDR certification programs that measure metrics like peak brightness, the new Adaptive Sync Display Conformance Test Specification (or Adaptive Sync Display CTS) is designed for variable refresh rate displays to prevent glitches such as flicker and dropped frames.
Variable Refresh Rate (VRR) is a technology that allows a monitor to synchronize its refresh rate with the output of any device plugged into it, reducing the appearance of visual artifacts, screen tearing, and frame pacing issues. When support for VRR first appeared on graphics cards and monitors, it was often tied to a specific manufacturer: Nvidia’s G-Sync and AMD’s FreeSync. But in 2014, VESA built native Adaptive-Sync support in DisplayPort 1.2a based on technology provided by AMD, and it is now a standard cross-compatible with graphics processors from all three manufacturers: IntelAMD and Nvidia.
Nvidia and AMD have conducted certification tests against their own standards
Nvidia and AMD have long offered their own certification schemes for VRR displays 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 in 2019 as part of its “G-Sync Compatible” program, only 5.56 percent of the models it tested actually passed. They either don’t offer a wide enough refresh rate or have other image quality issues like flickering.
VESA’s new certification aims to provide similar assurances for Adaptive Sync support for monitors or laptops. But unlike Nvidia or AMD’s certification, it’s an open-source industry standard whose testing criteria are public.
“GPU vendors obviously have proprietary standards, but they never disclose the full scope of the tests,” Roland Wooster, an Intel engineer and chair of the VESA task force who proposed the new tests, told me on a Zoom call. Looking at Nvidia’s website, for example, you You’ll see that it says the monitor needs to pass over 300 tests to get the G-Sync logo, but it’s less clear what exactly those tests are. This has created some confusion over the years, especially when it comes to standards like “realistic HDR”.
‘They never disclosed the full content of the test’
With its certification, VESA is testing raw Adaptive-Sync performance, not GPU-specific standards like FreeSync or G-Sync. For this reason, VESA expects its certification marks to be frequently juxtaposed with manufacturer-specific equivalent marks. The G-Sync logo tells you how your monitor is performing on an Nvidia GPU, but the VESA AdaptiveSync logo tells you how your monitor is performing on any Adaptive-Sync capable source.
Importantly, VESA’s Adaptive Sync technology only works with its own DisplayPort standard, which is available for monitors and laptops (including when streaming video over USB-C). Unfortunately, it doesn’t help you pick one from the growing list of TVs that offer VRR support via HDMI 2.1, which are more of a Wild West standard.
However, in addition to being more public, Wooster suggested that VESA’s new certification standard would make monitors a higher bar than these vendor-specific certifications. “We’ve seen some displays certified for flickering, flickering and not meeting the gray-to-gray specs we have here,” he said. In a follow-up email, he told me that he expects less than half of the Adaptive Sync monitors on the market to be VESA compliant, similar to what Nvidia found when it launched its own Adaptive Sync Display certification.
Under VESA certification, the monitor can receive two compliance marks. MediaSync works with monitors you might use to watch video or create content, while AdaptiveSync works with gaming monitors. If their device passes these tests, the manufacturer is allowed to put the relevant logo on the product’s box, website, or anywhere it thinks potential customers might see it. Displays that fail the test cannot use the flag, but the manufacturer is not required to publicly disclose the failure.
MediaSync logo, focused on video playback.Image: VESA
The AdaptiveSync logo is for gaming monitors.Image: VESA
The first of these two logos is called MediaSync. The point here is to make sure the monitor can handle the 10 major international frame rate standards (23.976, 24, 25, 29.97, 30, 47.952, 48, 50, 59.94, and 60fps — 23.976 is usually typical for US film content). This may sound like a simple problem, but 24fps content can present a real problem when playing on a 60Hz monitor, as the frames aren’t evenly divided into the screen’s refresh rate. The three-two pulldown is the usual way to deal with the problem (twice for the first frame, three times for the second, two times for the third, and so on), but it produces an unpleasant jitter. The MediaSync logo means that the monitor can use Adaptive-Sync to avoid any such issues.
The second is the AdaptiveSync logo for high refresh rate gaming monitors. So, for starters, a monitor with the AdaptiveSync logo needs to be able to run at native resolution at a maximum refresh rate of 144Hz or higher in factory default mode, and its adaptive refresh rate needs to be able to drop down to 60Hz. That doesn’t seem like a very low floor, but Wooster explains that if your frame rate drops lower, say 58fps, the monitor will hopefully use frame multiplication to bring it up to 116fps and bring it back to adaptive. Sync range.
If the monitor can go up to 144Hz, you’ll see a “Display 144” box to the right of the certification logo, but Wooster told me that this number will reflect the monitor’s maximum refresh rate — whether it’s 144, 240, or 360Hz — native resolution Rate.
thorough and open approach
Just being able to display frame rates in this range is not enough. To be certified, the display needs to be able to do well. This means that even if the frame rate of the monitor changes rapidly, it will not show a level of flicker visible to the naked eye. This means no dropped frames – which happens when the monitor provides an input that supports a higher frame rate than the panel actually supports.
VESA also takes a detailed approach to measuring response time, or the time it takes for a display pixel to update. Across the industry, it’s often expressed as “gray-to-gray” response time, or roughly the time it takes for a pixel to change from one shade of gray to another. If the response time is too slow, the display may experience “ghosting”, where the remainder of the previous image is still visible on the screen as the pixels struggle to keep up. In order to get the AdaptiveSync logo, the monitor’s response time must be less than 5ms.
5ms seems higher compared to the 1ms response time that many manufacturers claim their monitors are capable of.But in real-world tests, such as by ringthe response time is generally much higher than 1ms. ring Any response time below 6 milliseconds is generally classified as a “good value”.
Manufacturers like to claim about 1ms response time because their tests are not as rigorous as independent reviewers ring or VESA’s test center. Wooster said some manufacturers may perform some gray-to-gray changes and pick out the best results. Others may benefit from the fact that a warmer panel can respond faster than a cooler panel. Overdrive can be used to achieve faster response times on paper, but at the cost of ugly visual artifacts.
The first certified monitors will be added to VESA’s list today
VESA’s solution was to measure a variety of different gray-to-gray transitions (20 in total) and average them, rather than picking the best result. Testing is performed at ambient temperatures between 22.5 and 24.5 degrees Celsius (72.5 – 76 degrees Fahrenheit). The monitor has time to reach a stable temperature first, and limits the amount of overshoot and undershoot that the monitor can show and still pass.
Wooster declined to say how much he expects to pay for a VESA membership for a device that eventually gets MediaSync or AdaptiveSync certification (the fee is the same whether the monitor passes or fails), but the first certified monitors should appear in VESA starting today. on the website. He cited the number of devices that are currently one of the VESA HDR certified as an example of the number of monitors and laptops we might eventually see with the new AdaptiveSync logo.
Considering that VESA has a large roster of members from across the monitor industry, these little orange and blue logos will quickly become a must-have quality sign when buying your next monitor or laptop.