What Is G-SYNC And What Does It Do?

You’ve probably heard of G-SYNC. You will find it in most high-end gaming monitors. You will also find that G-SYNC monitors are usually significantly more expensive than the gaming monitors without it.

So, what exactly does it do, and is it worth it?

What Is G-SYNC?

G-SYNC is NVIDIA’s technology that synchronizes a monitor’s refresh rate with a graphics card’s frame rate in order to improve the gameplay performance.

All GeForce GTX graphics cards starting from the GTX 650 Ti Boost support G-SYNC as long as you have a G-SYNC compatible gaming monitor.

Unlike standard gaming monitors, G-SYNC displays have a special module installed in them that enables the variable refresh rate. This also raises the price of the monitor by $100-$400 depending on the model.

G-SYNC Compatible FreeSync Monitors

On January 2019, NVIDIA launched a driver update which allowed GTX 10-series, GTX 16-series, and RTX 20-series (or newer) graphics cards to utilize variable refresh rate over DisplayPort on FreeSync monitors.

In September 2019, NVIDIA partnered with LG in order to enable variable refresh rate on LG’s C9 and E9 OLED TVs over HDMI 2.1. Further, some G-SYNC gaming monitors, such as the Acer Predator X27P, have started appearing that support VRR over HDMI 2.0 as well.

Additionally, future G-SYNC monitors will support both HDMI-VRR and Adaptive-Sync over HDMI and DisplayPort. This will allow you to use VRR on a gaming monitor that has an integrated G-SYNC module (v1 and v2) using an AMD graphics card or a compatible console.

So far, numerous displays have been certified as G-SYNC compatible by NVIDIA meaning that those FreeSync displays are guaranteed to work without any flickering, visual artifacts, excessive ghosting, or other issues.

Other FreeSync monitors may also offer VRR (variable refresh rate) for compatible NVIDIA cards, but the quality of performance isn’t guaranteed. Depending on the monitor, it might work fine, work to some extent, or not work at all.

This will also vary between different units of the same monitor, just like one unit of a certain monitor can be overclocked 10Hz+ over the specified maximum refresh rate while another unit cannot go even 1Hz over it.

Most monitors will, in fact, operate just fine with only minor and tolerable (if any) issues. You can check out our list of all FreeSync monitors we’ve tested that provide a stable G-SYNC performance.

There are several things you can do if you’re having trouble with getting FreeSync to work on your NVIDIA card.

• Use DDU (Display Driver Uninstaller) to completely remove the old drivers and do a new, fresh install.
• Update to the latest NVIDIA drivers. You will need at least version WHQL 417.71 for FreeSync to work, but newer updates may contain certain useful fixes.
• Use CRU (Custom Resolution Utility) to increase or decrease the variable refresh rate range.
• Use RTSS (RivaTuner Statistics Server) to limit your FPS (Frames Per Second) rate to at least 2 frames below the monitor’s maximum refresh rate.

You may also need to turn on/off your monitor to activate G-SYNC on FreeSync monitors. Try fiddling with both FreeSync modes (basic and extended) if the monitor has two modes.

The most common issues include screen flicker/stutter when the FPS/Hz rate drops below the dynamic range and triggers LFC as well as having to power cycle the monitor too often.

What Does G-SYNC Do?

Traditional monitors operate at a fixed refresh rate, commonly at 60Hz, 100Hz, 144Hz, etc. This means that the display is refreshing the screen 60 times (if it’s a 60Hz monitor) in a second to create the image.

Naturally, for the image to be created in the first place, the GPU has to render a certain amount of frames and send them to the display.

If the graphics card isn’t powerful enough to keep up with the monitor’s refresh rate, you will experience screen stutter in video games. In case the card sends out more frames than the monitor’s refresh rate, you get screen tearing.

There are several ways to prevent the above-mentioned issues, but none of them are as effective as G-SYNC.

V-SYNC (Vertical-Sync)

In essence, G-SYNC is an improved version of VSYNC. You can find VSYNC in the display driver settings or in video game settings.

Enabling VSYNC makes the GPU hold the frame until the monitor is ready to display it. This will eliminate screen tearing but will increase input lag. This even happens on the higher refresh rate monitors, but the input lag penalty is much lower on these displays.

When VSYNC is disabled, then the GPU sends frames to the monitor as soon as they are rendered, regardless of whether or not the monitor has finished its refresh cycle and is ready to move on to the next frame. This causes screen tearing if things become unsynchronized.

How Does G-SYNC Work?

G-SYNC allows the display’s refresh rate to change dynamically according to the intensity of the work required by the graphics card.

By doing so, G-SYNC eliminates screen tearing and stuttering for good as long as your FPS (Frames Per Second) rate stays within the range of the dynamic refresh rate which starts at 30Hz/FPS and goes to the maximum refresh rate of the monitor.

Of course, this also means that if your FPS rate suddenly drops below 30, you will experience screen stutter in which case you may want to lower the in-game picture settings if it occurs too often.

ULMB (Ultra Low Motion Blur)

While G-SYNC provides a smoother gameplay experience by eliminating screen tearing, reducing stuttering and decreasing input lag, it does not affect motion blur.

That’s why most G-SYNC gaming monitors (not all of them!) also have a feature called ULMB available. When enabled, this technology strobes the backlight in order to reduce the perceived motion blur.

Note that ULMB works only at certain given fixed refresh rates such as 100Hz, 120Hz, etc and that it cannot be activated at the same time as G-SYNC. What’s more, enabling backlight strobing reduces the monitor brightness.

ASUS developed a technology which can simultaneously run VRR and backlight strobing called ‘ELMB-Sync’ which is available on some of their gaming monitors from the TUF lineup.

G-SYNC Ultimate

NVIDIA rebranded ‘G-SYNC HDR’ to ‘G-SYNC Ultimate’.

Basically, G-SYNC Ultimate brings support for HDR (High Dynamic Range) gaming with minimal input lag while keeping all the original advantages of G-SYNC.

Learn more about G-SYNC Ultimate and High Dynamic Range.

NVIDIA G-SYNC vs AMD FreeSync

If you have an AMD graphics card, you should look for a G-SYNC certified FreeSync display or an ordinary gaming monitor with AMD FreeSync instead.

FreeSync monitors don’t have a dedicated module inside of the display, so there’s no extra cost involved.

However, FreeSync monitors usually have a more narrow dynamic range. For instance, a 144Hz G-SYNC monitor has a 30Hz-144Hz dynamic range whereas a standard 144Hz FreeSync monitor will usually have a VRR range of 48-144Hz.

Of course, there are exceptions where a FreeSync monitor will have just as wide dynamic range as the G-SYNC counterpart. Most of FreeSync monitors also support the AMD LFC technology which ensures smooth performance by multiplying the refresh rate when your FPS rate drops below the dynamic range.

For instance, if a FreeSync monitor has a 48-144Hz VRR range, and you get 47 frames per second, the display changes the refresh rate to 94Hz (double the frame rate) for a smoother performance. G-SYNC displays do this as well.

Lastly, all G-SYNC displays support variable overdrive which allows the response time overdrive to be dynamically changed according to the current refresh rate. This eliminates ghosting at high frame rates and pixel overshoot at low frame rates.

FreeSync monitors, on the other hand, cannot change the response time overdrive dynamically. So, if you apply aggressive overdrive, and your frame rate drops, you will get pixel overshoot. Luckily, this won’t happen often.

There are some FreeSync monitors, such as the Nixues EDG27S v2, with adaptive overdrive which works similarly to the variable overdrive.

But then again, there are certain FreeSync monitors that cannot simultaneously run FreeSync and aggressive overdrive, though in most cases, the highest overdrive setting is unusable anyway as it introduces too much overshoot.

In short, FreeSync is the best way to go for gamers on a budget while G-SYNC is for those who want premium quality and are willing to pay for it.

G-SYNC System Requirements

NVIDIA G-SYNC requirements:

• G-SYNC capable graphics card – minimum GTX 650 Ti Boost
• G-SYNC capable monitor
• DisplayPort 1.2

NVIDIA G-SYNC Ultimate requirements:

• G-SYNC capable graphics card – minimum GTX 1050
• G-SYNC Ultimate capable monitor with at least 1,000-nit peak brightness, DCI-P3 color gamut, and full-matrix backlight
• DisplayPort 1.4
• Variable overdrive, refresh rate overclocking, and ULMB

List of G-SYNC Compatible FreeSync Monitors

Note that the monitors listed above will work without any issues, such as flickering, excessive ghosting, and other visual artifacts, with compatible NVIDIA cards.

Other FreeSync monitors may support VRR with NVIDIA cards as well, however, in this case, the performance quality is not guaranteed – they may work just as good, not at all, or have certain issues.

See our list of FreeSync monitors to see which monitors (that we tested) provide stable G-SYNC performance, even though they’re not certified by NVIDIA.