FreeSync&G-Sync: What You Need To Know
Adaptive sync display technologies from Nvidia and AMD have been on the market for a few years now and gained plenty of popularity with gamers thanks to a generous selection of monitors with plenty of options and a variety of budgets.
First gaining momentum around 5 years ago, we've been closely following and testing both AMD FreeSync and Nvidia G-Sync and plenty of monitors packing both. The two features used to be fairly different, but after some updates and rebranding, things today have synched the two pretty nicely. Here's an update on everything you should know as of 2021.
The Skinny on Adaptive Sync
FreeSync and G-Sync are examples of adaptive sync or variable refresh rate for monitors. VRR prevents stuttering and screen tearing by adjusting the refresh rate of the monitor to the frame rate of the content on the screen.
Normally you can just use V-Sync to lock the frame rates to your monitor's refresh rates, but that introduces some issues with input lag and can throttle performance. That’s where variable refresh rates solutions like FreeSync and G-Sync come in.
FreeSync monitors use the VESA Adaptive-Sync standard, and modern GPUs from both Nvidia and AMD support FreeSync monitors.
FreeSync Premium monitors add a few more features like higher refresh rates (120Hz or greater at resolutions of 1080p or higher) and low framerate compensation (LFC). FreeSync Premium Pro adds HDR support to that list.
G-Sync uses a proprietary Nvidia module in place of the usual display scaler and offers a few additional features like Ultra Low Motion Blur (ULMB) and Low Framerate Compensation (LFC). As a result, only Nvidia GPUs can take advantage of G-Sync monitors.
In early 2019 after Nvidia began to support FreeSync monitors, it added a few tiers to its G-Sync certified monitors. For example, G-Sync Ultimate monitors feature an HDR Module and the promise of higher nits rating, while regular G-Sync Monitors only feature adaptive sync. There are also G-Sync Compatible monitors, which are FreeSync monitors that Nvidia has deemed "worthy" of meeting their G-Sync standards.
The basic goal of both G-Sync and FreeSync is to cut down on screen tearing through adaptive sync or variable refresh rate. Essentially this feature informs the display to change the monitor's refresh rate based on the framerate put out by the GPU. By matching these two rates, it mitigates the gross looking artifact known as screen tearing.
The improvement is pretty noticeable, giving low frame rates a level of smoothness on par with 60 FPS. At higher refresh rates, the benefit of adaptive sync is reduced, though the technology still helps to remove screen tearing and stutters caused by frame rate fluctuations.
Picking Apart the Differences
While the benefit of variable refresh rates is more or less the same between the two standards, they have a few differences outside of that single feature.
One advantage of G-Sync is that it continuously tweaks monitor overdrive on the fly to help eliminate ghosting. Every G-Sync monitor comes with Low Framerate Compensation (LFC), ensuring that even when the framerate drops, there won’t be any ugly judders or image quality issues. This feature is found on FreeSync Premium and Premium Pro monitors, but isn’t always found on monitors with standard FreeSync.
Additionally, G-Sync includes a feature called Ultra Low Motion Blur (ULMB) which strobes the backlight in sync with the display’s refresh rate to reduce motion blur and improve clarity in high-motion situations. The feature works at high fixed refresh rates, typically at or above 85 Hz, though it does come with a small brightness reduction. However, this feature can’t be used in conjunction with G-Sync.
That means users need to choose between variable refresh rates without stuttering and tearing, or high clarity and low motion blur. We expect most people to use G-Sync for the smoothness it provides, while esports enthusiasts will prefer ULMB for its responsiveness and clarity at the expense of tearing.
Since FreeSync uses standard display scalers, the compatible monitors often have many more connectivity options than their G-Sync counterparts, including multiple HDMI ports and legacy connectors such as DVI, although that doesn’t always mean that adaptive sync will work over all of those connectors. Instead, AMD has a self-explanatory feature called FreeSync over HDMI. This means that unlike G-Sync, FreeSync will allow for variable refresh rates through HDMI cables version 1.4 or higher.
However, the HDMI and DisplayPort conversation takes a slightly different turn when you start discussing TVs, as some G-Sync compatible televisions can also use the feature through an HDMI cable.